The only thing about Rumble that looks like Rumble are the weapons. The mould and colours looks more like G2 Smokescreen to me.

Not thrilled about Rumble's colours -- it's not black and red as the original Rumble was, nor is it purple and lavender as G1 cartoon Rumble was... nor navy blue like the colours of G1 Frenzy (and latter IDW Rumble). But I must admit... G1 colour bias is irrelevant, since TF Prime =/= G1. And quite honestly, some of these characters don't look that good in their G1 colours anyway, e.g. Arcee.

I think Airachnid looks nice -- but it's hard to tell with these digitally enhanced images. It'll be easier to judge once we see unaltered in-hand photos, and of course, when we see the toys IRL in stores or at meets etc. I don't mind getting toys of characters who don't appear in the show, so long as they're good toys. In theory these toys should be better designed that the show characters because they'll be unhindered by trying to conform to show likeness. Look at the movie toys - some of the better toys were ones designed by HasTak and not based on Paramount/Dreamworks' designs where they're trying to engineer some massively complex CGI model with 10,000+ components into a small action figure within a controlled price point/budget.