Surface Inflate - Version 1.1.0 update : Bezier Curve Mode (free addon)
This update add a new mode into the tool : Bezier Curve mode
You can select any faces, all of them will be inflated.
The shape of inflation is controlled by Bezier Curve (it can be tweaked by 4 parameters).
https://kushiro.gumroad.com/l/inmas
This is a free addon.