I couldn't love a TTRPG system more.

Player POV:
You can learn this system in 5 minutes. The entire PDF is 7 pages, and 2 of those are the equipment list and some GM-facing stuff. If you cut out all the (very helpful) examples and illustrations, "how to make and play your character" would probably fit on 2 pages.

But that's not why I love this system. I love it because it's the only one I know where you can play your character exactly as intended, every time. No more picking spells off a limited list, no more waiting until level-up to unlock your central abilities. No more warring with the rules of game balance.

You can play whatever weird, niche, multitalented character you have in mind, all their stuff is available immediately, and none of it will break the game.

Game Master POV:
Do you hate prep but love running? Cause that's me. I'd run every day if I could, but trying to balance all the cool stuff I want my villains to do versus the player's stats and counter-abilities gives me a migraine. 3 Bones eliminates that problem entirely. The villains are just as flexible as the heroes.

In this system, you can run a mind-controlling overlord for the party's very-first adventure, and they can handle it. But that doesn't mean the PCs are overpowered, it means the system is flexible. You could also run a gang of goblins at the same difficulty setting. 

And if you still feel attached to the monsters and settings of your previous system, you can still use them. Translating a monster, item, or whole adventure into 3 Bones is so easy that even I, a hyperactive anxious wreck, can do it on the fly.

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I truly can't shut up about this system. I've been using it for everything. 3 Bones is elegant in its simplicity, and everyone should try it.