I'm so glad you suggested this! I made an account just to post something similar because I really feel it would benefit the game and add even more replayability to it!
The game Don't Starve has a similar 'toggleable' menu that lets you choose between 'off, less, default, and more' for all factors at the start of a new game including:
spawn rate of various resources (i.e in Niche this would be berry bushes, trees, fish, bunnies, etc)
enemies (balance bears, bearyenas, artic foxes, apes, etc)
weather (rain, sun, etc.)
other factors (creature lifespan length, number of wanderers, number of rogue males, # of ice tombs generated etc).
This really lets you customize your game play and improves the longevity of the game. It would allow us to tell more stories, like say you wanted to simulate a drought and have your creatures survive, or do a minimal resources survival run. It would also let people customize the game for their own play style. For instance, I don't like the spawn rate of the balance bears. My tribe of 15 has killed over 6 of them, I would definitely choose a lower spawn rate for them if I could. I don't want to eliminate them, I just don't enjoy being chased constantly.
Also, sometimes I just want to play a relaxing game, and it would be nice to put the game on easy mode with high resources and just chill out and breed nichelings that look cool!
I've attached what the toggle menu from 'Don't Starve' looks like. It's just picture icons of the various resources/options, with the toggle selection for each.