I don't think Paradox pushes studios working for them as a publisher too hard; rather, I think in the past they wanted to support new/indy studios too much. Basically trusting their scheduling and ability to push in the final product. I like Sword of the Stars II very much, but the release fiasco was Kerberos' fault. They lied to Paradox that they had a finished product, then uploaded unfinished shit to Steam. They had some good reason for it, losing important personnel at a bad moment during development etc, but it was their fault for not informing Paradox at time and changing release date accordingly.
I was dubious regarding Kerberos already at the time due to their utterly arrogant fan interactions on their forums - basically their head honcho calling anyone disagreeing with game design decisions stupid and smelly poopoohead - but releasing unfinished crap was quite unforgivable. I'm glad I didn't pre-order. That being said, when their free DLC came out, the game was in a playable state. They fought to fix it and I respect that, even though the finished game still lacks 20% of the things it was supposed to include on day one. (Intelligence actions do nothing, government forms do next to nothing, diplomacy is minimal, non-existent internal politics etc.)
Anyway, I think Paradox learned a lot from these mistakes. They've still given a chance to new studios as publishers, but don't take as much shit anymore, as is visible from the amount of canceled projects. I mean, they even canceled Johan's love child Runemaster after realizing it wouldn't work as designed. Killing your darlings is always hard and honestly that game sounded interesting.