Great game and really fun, though obviously being in alpha there are plenty of problems to iron out and most likely a lot more content coming eventually. As an up-and-coming gamedev myself, I understand how much work this project likely is. That being said, I do have a few suggestions that it'd be nice to see you implement as long as it's not too hard:

-More bosses (2-4 per floor, maybe even 5, probably following the same design schemes as current bosses (similar to regular Isaac bosses but different))

-Some sort of proper boss splash intro screen

-Maybe another floor or floor variants of some sort

-Minibosses (harder enemies that have a small chance of spawning, only one per level or possibly per floor, could be the sins or horsemen or something else)

Once again, while these would be great to see, I know how painful the development process can be so don't feel too pressured!

Great game. To balance out the overwhelming demand for more slots, I think that the 4 slot limit is great. It's limiting in a good way. As for suggestions, I had one idea. What if, every time you added a baby to the game, the method to unlocking it is a secret. Like, don't even give a hint that it's in the game. It would lead to avid fans searching for random things to do, and then sharing that answer with other people. I think it'd be a cool thing for people in the community to theorize about, wondering how many hidden babies are out there. Kind of like what is currently in the game for the brown ritual, but more likely to occur naturally. For example, you put dark bum in the game and the way to unlock him is to let 500 points worth of hearts despawn. No hints, just let people make their own discoveries and share the findings. I think it'd be fun.

what if there were multiple starting babies for each type and each had a slight difference

(I only have shooter so far)

Brother bobby (better firerate) OR Sister Maggy(better damage) (more possibilities? )

Highlight items you have not yet seen. It will make 100%-ing the game a bit easier

add Yum Heart as an activatable that gives you a reserve of hearts at the moment and that increases every time you use it in one level, when you move to the next the accumulation of hearts will restart

based on the Item of Inner Eye and Baby Brother create an approximate to the Inner Baby, which in exchange for tears, attacks 3 rows at the same time, but also has a slight increase in damage.

maybe you could add the buddy in a box? it could be something like random buddy but instead of every tear being random, every baby has a random effect.

maybe also a mysterious liquid baby, but im not a programer, so im not shure if any of those two could be possible

incredible game btw!

add as an active item the necronomicon, simple, when using it causes damage equal to 6 hits of brothers baby's

will act as an improved power up pill, in exchange for its use, the recharge of the usable item will be lengthened more for each use

gives you a random resource, pill, coin, mini hearts or hearts and very very very unlikely a passive or active item

gives invincibility to a baby that you choose but will avoid shooting, in return you can perform the effect to allied enemies (Gapper, Fatty, etc.) and will be given invincibility, and instead of the babies can attack.

Passive Item

Flat File

Effect : removes spikes on the Ark levels and you can put babies in their place

Price:(not sure)

As an option, it can be opened for 10 Spike Babies killed by a shovel or monsters

Petrifying baby, does not attack, being placed in a row, will infrequently petrify all the enemies of that particular row for 2-3 seconds

baby scissors, mechanics based on the carnivorous plants of pvz, will attack a single frame in front of it and after attacking will have rest/recharge time to attack again

Hide health bars of Spider Mod for entities have full HP. They are annoying

When selecting babies after level there is a row of already obtained babies at the bottom, same row of obtained items at the top would be very useful, to fully understand what combinations one can do.

Red Showel + Candy Heart synergy = on removing baby get full hearts back.

Discord dead lol

maybe we can get some items permanetly?eg slightly increase babies' CD or damage...

AND,nerf Hardy PLZ!!!!!!!!