As money seems to be a driving factor of this discussion: we're looking at turning over around �250k this year.
We use Construct 2 for 2D work. We use Unity for anything 3D.
Currently we're working with one of the biggest casual publishers to distribute Mortar Melon on iOS, Android, Windows Phone, Windows 8, Blackberry 10, Tizen, Firefox OS, web, PC, Mac and Linux. For our publisher to anywhere near break even, Mortar Melon must earn �100k in sales after store cut.
Hopefully that highlights some of the revenue potential.