I've been fascinated by Spanish Civil War ASL ever since I got involved in a discussion about a projected HASL for it, back in the ASLML days.
I think both SCW and KW would work in ASL, and I would not object to either. I have yet to play any of the existing SCW scenarios, and I've played one KW scenario (Obong-Ni).
I voted for SCW because my (limited) reading about KW battles makes them seem pretty monochrome, terrain-wise and troop-wise.
Even though I don't need or want more ASL counters, I would actually prefer to see the SCW done with new counters, because I think it would be hard to do it justice while sticking to existing limits. Either you use one WWII nationality per side, in which case it's not really SCW after all, or you use a riot of existing nationalities' counters for each side to get all the details right, in which case you end up with a confused mess.
What I do not want is to see three different producers come out with three different versions of the units and rules for the war -- either war. I would much rather have official rules for these things created through MMP, than have a CH version and a HOB version and a ___ version.
John