Belly buttons and belly button growth (for those with a navel fetish)

Pussy and clit sliders and growth

Nipple sliders and growth 

Different cock types

Cock + balls sliders and growth 

Cock, nipples and navel insertion (for inflatomax and mayhaps sex)

Sweat

Null bulges (also for those into it)

Vore (ALSO also for those into it)

This specific image in the top right corner of the bathroom area in the gatherers guild (because funny)

Liposuction machine as it's nearly impossible to lose/reset weight without restarting at the moment (as a 5ft caith, it took 54 years of standing still to get from 4300lbs to 140lbs, and ~15 minutes irl via autoclicker, while it only took 60m to get that big)

Some indication of how much each weight gain speed option affects gain (default = 1x, realistic = 0.5(?)x, ludicrous = 16(?)x)

Presets for skin and hair colour

Weirder intruments for voices (theremin, glass armonica, daxophone)

Hey, great game! Perhaps you could add some muscle growth stuff, like, mixed with bulking up mechanics.

Another idea I had was fartflation. (Either the npcs getting fartflated or you)