Wait, the show got cancelled or Milana Vayntrub got cancelled? Because I just saw her in a low-budget remake of Clue called Werewolves Within. While she’s lovely enough for a memorable five-second sequence dancing around in a low-cut shirt to the one song they could afford to license, and while she can hold her own doing playful banter with the awesome Sam Richardson (who’s an extremely generous actor!), I don’t think she’s lead material for a superhero series. I guess it would have come down to the squirrels. Are we talking dopey CG squirrels, or actual live action squirrels? If it’s the latter, I’d be there just to watch the logistics of squirrel wrangling. From @forgeforsaken’s picture, it looks like the squirrel is a puppet?
But I’m guessing you mean the show was cancelled, so we’ll never know.
All this reminds me that I should boot up Marvel Ultimate Alliance 3 and see if they’ve added any new stuff in the last several months. For all I know, there might be playable Squirrel Girl in there now!