Can't remember where I read this on tumblr, but I read a critical post that basically describing that Viv couldn't realistically end her shows because she was effectively Typecast/shipwrecked with the Helluaverse. Even if spindlehorse where to start a fresh project like Zoophobia or Homestuck, it wouldn't find much success with Viv at the creative helm. (Or in the case of Homestuck being associated with her because of the constance swearing.)
Personally, I believe that at some point (sooner or later) Viv is about to hit her career peak and fall similar to that of Butch hartman, in the sense that people won't care anymore because of all the goodwill burnt up from their lacking creative talents and personal actions. (honestly I think you could make a whole different post comparing the two on how similar they are).
While it's 100% true I don't think she will be able to pivot into any other show or series due to her reputation she has made for herself in the real world of studio production. Anything she wants to do moving forward will be through her own studio and own finances, but I expect Spindlehorse/SpindleRoo to close down in the next 5-15 years and Medrano goes back to where she was before all this: Making comics.
I also expect her not to finish any of them.
I don't see Medrano being any more relevant than Hartman or Astruc once her moment fades.