I absolutely loved the game, though it was a bit a slow at times. The game itself is nice but the pacing feels a little sluggish in the cave section even with max out research and upgrades. Aside from that the gameplay works really well; the weight gain mechanic also doesn't remove from the gameplay with how nicely it ties in with the mechanics. The sizes are great and I just wish there were more!
On a side note, once the game is in a state you're happy with do you plan on adding any end game content or new things to play with afterwards? Oh! I also wanted to know if you've considered adding body inflation and not just keeping the game tied to weight game, kind of like how Tribal Hunter is.
Anyways keep up the good work with the game; you did a great job making a fetish game, I'd give it a 8.9/10!