If you have anything above Tionese, SM puts you to sleep it seems.
As far as 16m HM (I've yet to bother with 8m HM), Columi really is probably enough, though maybe your tanks may want some better gear. The gear check isn't that hard. It gives you a bit of breathing room if you are slow getting on targets, but if you aren't, there isn't really an issue. WIth BH gear across your ops, you probably are fast enough to skip or trivialize certain parts. I've done 16m HM with most of the group in augmented WH/EWH (including tanks) and it's not really an issue.
That said, I can certainly understand wanting people to overgear it you happen to be pugging, though the encounter is simple.
I tried Xeno 8m HM with my sorc dd in columi gear and it didn't quite work. It was an alt run from my guild and I don't remember how the others were geared, though columi really is not quite enough. I mean, HM does drop T5, so, yeah.