The purpose of the Incubator Program is that Tapas funds you to create a Premium series. It would be hard for them to make back their investment if they paid you to make a comic for free. ^^;;
As for the legal stuff - you're right, every contract is different! We've been pretty happy to speak openly about our experience working with the Tapas team as part of the Incubator. Tapas is easy to work with, they're patient, open with communication, and they never want to do anything that makes you uncomfortable.This was our first ever contracted work, so we were fairly cautious about it, too, and did a LOT of reading around and research before we decided to accept the deal. I'm so glad we did.
This October makes one year since we've been participating in Incubator, and I have to say it's been a wonderful experience. Doors have opened for us professionally that we never thought possible, and it's a great opportunity for anyone serious about becoming a professional comics creator. Like I mentioned previously, Archia and I used to do self-publishing and patreon, and we made our money through those avenues. We've definitely gained from our relationship with Tapas in more ways than we could have imagined and it's a shame if people don't give this program a chance based on some hearsay from people who've never even published on Tapas, nevermind been a part of Incubator.