A small update. I decided to start with the arms and wings.
Most of the purple pieces are staying purple, but I still wanted to give them a painted look, so I painted over them (the claws and wings) with a Transparent Purple lacquer (by SMS). It gives them a richer, deeper colour.
The one on the left is painted, the right one not. It's a bit more vibrant in real life.
The grey parts I wanted to look similarly, so I painted them with a transparent smoke (by Alclad), but it darkened them way too much, almost black. I did a fine coat of a mixture of Polished Aluminium and Steel, both Alclcad metallics. Came up nice.
I also base coated the 'hand' bits of the claws (they will be going from pale aqua to gold on the finished model) with a Gloss Black Base (Alclad again).
Finally, I wanted to try out a Transparent Orange (SMS) on the scrap piece of clear plastic I removed from the MP Seeker stand to see how it behaves. Learned a few lessons, mostly make sure I do a deep clean of my airbrush before using it. But I am happy with how bright it came out, with several very thin coats (like about 5-6 passes).
Total time taken so far: 3 hours 40 minutes.