In that price range the Flux is probably your best bet. Personally I don't think it's notably smoother than the MH1C but it definitely has a bit less bass and a more accurate overall sound. The cable on the Flux isn't great but it's symmetric and can be used over-the-ear. It does have a mic though. Staying in the price range there's just not much that can compete with the MH1C, especially considering you like the signature. Moving up into the $100-$150 range there's more options but nothing I can think of that ticks ALL the boxes per your requirements.
I bought the Flux and have been listening to them for a while, I like them more than MH1, Flux seems more balanced, mids and treble are more present but not disturbing. I've been reading a lot about iem and sound signatures, of all the IEMs I owned, I really loved the Brainwavz M1, the Vsonic GR04 Flagship (apart from sibilance), the Sony MH1 and now the Flux. I also listened to Shure SE215 but for 5min, really smooth except for not that present treble, soundstage . I like the full bodied sound, smooth, without anythig in particular to disturb your ears (harsh treble, sibilance, too much bass, too much mids, to much lower treble etc.).
I guess that puts me somewhere between warm and smooth and balanced? Now I'm even considering an upgrade to the Flux.
I read about the Fiio X3 DAP these days, is it worth 200$ as upgrade to the clip+ ? Would I hear a noticeable difference in SQ with the Steelseries Flux for example or do I have to also buy 100-200$ IEMs to hear something?