I would like to just name a couple hard points that I have in mind on the subject, since others have the discussion part down pat:

-I like the attribute system idea. I would however like to request that the skills/abilities as we know them each remain - and that we can still manually level them up.

For the levelling system, I would like to defer to a diamond-in-the-rough in the world of gaming: The levelling system in Mount and Blade Warband. Each attribute affects what you do in a passive, small way, that can make a difference in the long run. However, to really bring out the power of that merit, one must level up skills as well as attributes; the skills and the attributes collaborate to make a powerful character.

The skills as we know them, I think should still be levelled up using Juice Fountains

Maybe you could "level up" when your stats reach max. It gives them a higher max but resets them.

Maybe you could "filter" juice into different types. Red would be for arm power, Green for flight and movement, and blue for health and stamina.

I definitely think that making the magic system separate will help stretch the game longer while feeling better:

Being able to do all the books at the start kinda feels overpowered on the various runs I done, especially being able to get them from the crates at the start in the school (which feels weird because I thought the school was supposed to be some pocket from the rest of the galaxy). Being able to "unlock" the ability to use spells by using juice in a more tiered manner would feel nice and add more variety to the leveling system. This could be done with two ways-

1. A more player controlled approach, with them basically learning to "read" the book by spending juice, this could be done for every weapon by giving the books each debuff and buffs depending on how good the player can "read" the book. Giving it half damage at a low tier and then giving a "crit chance" or "greater damage percent" would help not make it to where one stat controls all the magic, which would probably be liked because people also like being able to tweak the various physical aspects of the characters, so why not the magic system?
   1. Don' know where they would spend their juice at, perhaps a different fountain or a new NPC?
2.  Giving books a "unlock more power by completing certain tasks" which would make it more story/tasked driven. You would probably have to make it more of a binary system with just "you can't use this because you haven't explored/killed/helped [X] yet" (or a more subtle hint what to do).  
   1. This could encourage exploring or progressing the story, but it may make it feel to gated.

HOWEVER implement anything like these two things would make a lot of extra load with every new spell added; with the first approach suggested, you have to make tiers for every spell book and judge what would be the proper costs for each; with the second approach suggested, you have to make story beats and/or tasks kinda connected and judge what time accessing the spell would be that complements the average gameplay.

Really you can just ignore this because it would make a catastrophic workload for you, but with how the spells work now just shows me that it needs to have some limiting factors from the get-go and that it needs more tweaking of it's properties like how you can tweak your swing speed and damage with melee weapons and how you can tweak your movement with jump, fly, and movement speed.

I'm still going to be happy with whatever direction the game takes though with its iterations, hope the game-making process goes smoothly for you! (it's your project after all, not mine) ((also sorry for the horrible grammar and run-on sentences))

That is a ton of changes. I would love to see stat changes be more beneficial, but I am not sure that doing it ALL AT ONCE would bode well. Try doing pieces at a time so that you don't have to redo a whole bunch of stuff.

I am all for the no capacity stats, but add like a code with an exponential equation that increases the level up cost per each stat level. Like "LevelUpCost(x){ x^1.5}" where x is whatever the current stat is.

Something is charming about flying to monster level 50 and juice farming. Making stats purely use-based is a lot less fun, and also lessens the need for juice farming. If you want the infinite terrain to be a thing, you should also have the infinite stat to be a thing.

As you go farther, monsters gain size. What if you added size as a stat so we could actually reach monster hit boxes more effectively? Or size could increase residually as you gain more levels.

If you want to add a gets-better-as-used thing though, maybe apply it to weapons. Like weapons gain levels with each hit they get or something and have a max level depending on what rarity you found them with.

I think there is little use for jump height but spirit would be an absolute plus. Like extra spell damage or pineapple, rubber ball cannon, or frizzX damage. 

What you have done so far is really cool, fishlicka. Everything can always be improved, but I personally would not like to see the game changed so drastically.

what if you could infinitely spend/recover juice at the juice fountain to change your stats? similar to how you can enlarge/shrink weapons, sure there's "no maximum amount" but with the juice cost going up as you increase you may not want to go to infinity

however once you get to a "ugh everything costs too much so there's no point to any upgrades anymore" level, it'll run into the same issues as the current stats with there being not much to do late game

it's not flawless and honestly you're "level as you play" approach seems more fun, im just giving my little bit of feedback to my tired brain can come up with, hope it makes sense and i hope when you make the stat update you can be proud of it, because i sure will be!

I know you've had this thread up for a while; I may as well give it a cent or two.

I for one would like to suggest a slight upgrade chance for each stat- be they the new basic ones you've suggested, or more detailed/derivative ones- if they predominately or exclusively are invested in at the expense of others.

For example, if I invest entirely in haste, while neglecting all the other four stats, then after reaching a level with haste, haste from then on would rise a little faster with use, and/or be proportionately more efficient to "buy" via points. From then on, I can increase haste further, faster, whereas the other stats must be hard-pressed-for as always.

By contrast, if I were to balance my character, keeping haste in a stone's throw of each of the other stats, then no bonus (or penalty) would apply and the levelling system would work as it does by default.

Lastly, in this system I imagine, the more specialized the stat is, the greater the bonus for future levelling becomes. For example in the above... example, focusing solely on haste will give it a better bonus than, say, also investing closely in muscles; but, raising just those two would still give each a bonus if they can significantly outpace the other three stats. In turn, raising muscle and haste would give each of the two, when they get high enough, a bonus better than if I were to raise, say, muscle, haste, and sense together. Still, raising these three would incur a slight bonus if made high enough.

This would allow, and encourage, players to specialize a character in a particular way, if they choose. If anyone wants to make a juggernaut meathead that moves like a turtle but can take any hit and smash anything, including out there in the 300.0+ level fog, they may do so more easily; if we want to make a speed demon who can run from the graveyard to the cabin in about five seconds, and who simply runs circles around whatever threat comes along, we can push for that goal; and I don't know what "sense" will be about, but whatever it is I would like to try it and make a game mode/character exclusively revolving around it. Maybe you can do for this "sense" what Bethesda neglected to do for Illusion and Alteration in TESV. I certainly trust you more already.

y si tomamos el koaladog como mascota y podría atacar a los monstruos mientras y tambien podemos mejorarlo

and tame other monsters

so does that mean that eventually if the player uses flying a bunch (like most would) it would cause them to at some point fly extremely fast? or am I losing my mind here?

you should add defense like armor, resistance stat and maybe shield

and add teleport station cuase why not? by unlocking new area!

I like the idea, but it would be cool if that were integrated into the current system. Also, juice can probably be used as a currency (which can help create interesting player situations) but I think the current system is great and should be integrated to the ones you suggested. If the player scales, so should the bosses to keep it difficult. Also, I like the difficulty bar.

it's probably already been considered, but maybe a luck stat?

I think you should go with a class system, in the menu, you should have mage, warrior and ranger, and it should affect the price, or effectiveness of skills, and some other things, ranger will deal more damage with ranged weapons and upgrading damage and walk speed is better, warrior deals more damage with melee weapons, and upgrades swing force and health better, and mage deals more damage with runes and upgrades stamina regen, and stamina better. also, maybe each class has a special ability, like warriors having passive damage resistance, archers turning invisible when below 25% health, and mages having a spell casting familiar that can be equipped with runes but the spells do 50% damage and the stamina pool is half the size of the characters.