Yes. It's not crucial to me, I'd still stick to single player mostly.. but I'd at least try out multiplayer if it had all the single player features.
Multiplayer without tactical combat or quests or anything else that makes Elemental what it is, is not something I'm interested in at all.
Hotseat and/or pbem would also make it much easier for me to get into MP and maybe even get some friends to try it, these are mandatory to make MP really shine in a slow-paced TBS I think. Of course tactical combat doesn't really mesh with pbem, but missing tactical battles can be a worthwhile tradeoff for the convenience of pbem - we need the option to play it either way.
Really more options is what Elemental MP needs the most. There's nothing wrong with a stripped-down version meant to be played quickly and competitively (not something I'd really want to do, but I'm sure some would) - just give us the choice whether we want that or the full experience, whether we want tactical battles or not, whether we want pbem or not, etc.