Inflate and Stiffness behavior for soft body behaving objects in cloth simulation

So i use the new cloth sim quite a lot, but i struggle to get desirable results for more rigid objects. THe biggest problem is the inflation with pressure activated. The curves (somewhat similar to bevel segments behavior) are something i can hardly control.

As an example: and

For the edges, you would have more sharpness and close roundings instead of the big inflation forming on the middle. The base shape to retain is basically a round cube, stretched on the Z-axis.

So that leaves me with 2 questions:

  1. Is the base mesh shape the biggest factor?
  2. Do you have to handcraft all spring vertex groups and if so, what parts are important for this kind of soft body objects(?)?