I've become a 'mid convert. See:
http://ryanjordan.com/blog/2010/05/the-versatility-of-the-pyramid-as-an-ultralight-shelter/
But see also Skurka's discussion in his book. My current solo tent is a DuoMid, and the only thing that has remotely tempted me to stray is the TrailStar.
But about you:
My non-solo tent right now is a silnylon SuperMid. It's a stupendous palace for two, at less than 30oz seal-sealed. For three it's very roomy. It's quite "cozy" for four full-sized (ahem) adults, but is well within reason. It is surely big enough for two chubby adults plus a dog plus being able to cook inside and still have room to stow your gear and to change clothes while under cover from the weather without being double-jointed.
If you use trekking poles the SpeedMid has the same square footage as the SuperMid but is low enough to use a trek pole as the center pole (with a pole-jack or a rock under it). It's also much less expensive than the SuperMid, and 8oz lighter (in silnylon). Not being as steep-sided, though, the SpeedMid doesn't shed snow quite as well. But it might be more appropriate than the SuperMid if you never anticipate using it for more than two people- it would still be a palace for them. Or Oware makes an 8'x8' cuben mid, so it's a bit smaller than the 8.5'x8.5' MLD mids.
I personally have no issues with floorless tents, and I use a 5.5oz bivy instead of a groundsheet. It also keeps the bugs off if needed, and the snakes/wombats/pinnipeds out of your bag while you sleep.
Some people can't stand the center-pole thing, and I'll be honest and say that to me this like an outward sign of some sort of deep-seated psychological issue for them. Or something. (But in all seriousness, maybe I just don't get it because I'm not one of the center-pole haters. That center-poles drive some other people batty is a source of near-endless amusement for me.)
Mids are ridiculously simple to erect. They handle snow well. When closed they offer walls in all directions to deal with blowing variable rain. Fully guyed they shed wind nigh-effortlessly. With the door open you still get the great views (and great ventilation). You can pitch them high for ventilation, or low to inhibit rain spray or drifting show. You can pitch them over a snow pit in winter. They are very multifunctional- IMNSHO if you can only own one shelter it should be a 'mid.
They are also very practical in cuben, since you seem to have a cuben fetish. (Though I think the SpeedMid is silnylon only.) The Hexamid is ALMOST a 'mid, so I'd back you up on that one if you like it, but I'm a believer in keeping things roomy (especially with a female involved). Personally I'd get a floorless true 'mid, but the Hexamid is profanely light…