It's here that I come to a crossroads. There is a black fungus themed spell that creates a 1/1 black fungus. Do I unify the tokens and make all the tokens saprolings, all fungus, or a combination of both?

If this changes to Fungus tokens it becomes a 1 card align enabler.

But if it makes Saprolings it helps with collaborate! o.o

Are Saprolings really part of your concept here? If not, then Fungus tokens migth be the way to go - you could even have this produce the black tokens which would be a neat mix-up from how it would usually work.