I just tried the game for the first time. Here is some feedback.
1) Movement and mouse-usage seem pretty obvious/easy to figure out. Material collection appears useless.
2) I can only guess what the various "feedback" bubbles mean or how they work, although the "X" seems to indicate a monster who will be released (overpopulation).
3) It took a long while to find the character update screen. Due to that, I didn't raise my stats until I hit level 5.
4) Some traits are white, others are green. I tried breeding a "tall" monster, but have not yet managed it, so perhaps that function does not yet exist.
5) Walking and running are slow. I have not spent points on speed, so perhaps that is the solution.
6) It is difficult to get up the stairs (to my house) without running. Collision problem?
7) It is not clear what the different stats actually do. I tried increasing Vitality to extend the actions I can do in a day, but with no noticeable effect.
8) The first time I ran out of energy and face-planted, I fished around for some way to alleviate the situation. I eventually found the Game Speed setting and cranked it up to x5. My character did not get any energy back, and therefore did not revive, but the sleeping was eventually enforced automatically. The lesson learned was long and boring. I suggest either forcing the sleep mode at 0 energy, allowing slow movement at 0 energy, or allowing some means of returning home to sleep.
9) Speaking of sleep, the "Sleep Tight!" event is annoyingly drawn out with no way of skipping it. Perhaps add the option of skipping it with a mouseclick?
You might also include a Dev Mode where you can edit/experiment with stats. This would also be a nifty way to include "cheats," something that will eventually be added to the game, anyway.