Yes, I like that last version. Is that almost it for the swarm?
Instead of the racial bonus, why not make it Con-based? They're a bit sticky, right? Con would make sense if that's the source of the clinging.
I think most of the red question marks can go away. Those CRs look appropriate.
We'll need names for the groups. Does a term exist for a collective of slime?
Sounds good to me!A coagulation?
I guess 200 could work, but that's getting unwieldy enough a smart DM would shift over to the swarm version. Why not 3-30 like we already have there?