1 - That kit will serve you well for many years. I sill use the 400 XPR kit I've had for ten years now.

2 - I haven't done a lot of mesh work but I have used this stuff for a different application. Not a lot of transparency but easy to work with and breathes well.

3 - I've painted acrylic backplates with an airbrush, but only in opaque colors. I can highly recommend Wicked Colors paints for pretty much anything - airbrush or not.