One thing you might not have registered yet (there is a lot to take in).

Make some abs paint. Just mix acetone with abs off-cuts. This can be used to both paint different coloured abs on to models and to fill in gaps, smooth surfaces etc. As an artist you can probabyl find way more uses than I can.

Also if you're making a drinking vessel, a thickish paint can be used to make it water tight . It's also useful for gluing parts together.

Just useful to have a jar or two around of the colours you use most.

For a universal abs paint/glue/smoothing solution - make up some with transparent abs.