Attached Link: Not the latest, these are samples from v8 - check v9 too

for Painting: Project Dogwaffle, there's a free-for-home learning edition at www.thebest3d.com/howler/download

It's based on v8.2, the latest is v9

 

It also does some animation, lots of visual effects.

The top price is $89.

It's PC/Windows only.

It does layers but not opaque layers. Layers can be used for many things other than hiding other leyers behind it.

 

There's a free program called Paint.net that has layers.

There's also Pixarra Twisted brush, by Ken Carlino. His and PD Howler 8 are also in a www.CoolCreativeBundle.com bundle

 

Howler 9.1 is available here at Rendo.

Artrage is also a good contender. Good painting, not much in filters and 3D. Howler does have 3D for elevation map based terrains and other.