After having played through this game a few times in the past couple of times, I can say that it's silliness grew on me.
The whole evolving system worked really nicely (I was able to get most of the pigeon evolutions throughout my playthroughs), and the leveling never felt as if you were wasting points (except for two situations I'll address in a second). All the items served their purpose whether they were (seemingly) purely cosmetic or giving you temporary boosts to stats
At least for the current build of the game, I didn't run into any glitches; my pigeons always evolved unless I was spacing my stat points evenly, and I never ran into any issues with fights softlocking themselves. The two main gripes I had with the game were:
1. Speed felt extremely underwhelming as a stat. During battle, even getting attacked will cause your opponent to take damage, so building Attack and Defense ended up being better because you could either run through your opponent in a few hits or tank enough that they knocked themselves out
2. (And this one is more of a minor detail thing) Are the high level items supposed to be purely cosmetic? By the time I got them, I couldn't tell if they were doing much except making my pigeons look awesome
(Here's my first playthrough of it; I've since beaten the game with all unlocks)