Try enabling separate left/right actors, try reducing the sample radius or tweaking falloff, things like that.  TBH get used to the idea that full values of Pregnant and other really drastic morphs are never going to look good at full values unless you model the garment around that morph by hand - like in the real world, Spandex can only stretch so far before it looks crazy.  You can do fitting morphs by hand, but for the type of morphs you're talking about that's a ton of work.

My Freebies