I should've returned the damned model to GW. My GS skills were nowhere near doing the small detail work to fix all the parts on it. So I just did the ones I knew I could do. The spikes (read: Finecast tubes) were impossible. I just went ahead and cut the malformed ones off on the leg.
I started with just filling all the bubble holes in the mini and smoothing them out.
I have done some GS sculpting before but working with this level of small detail really requires steady hands and good nerves. And time.
I wish that after all this I can really give this mini a good paint job. Otherwise it feels just a complete waste of time and money.