To me, a "tent" is something fully enclosed on its own. (May not be bug-proof, though.) If it isn't fully enclosed on its own with a floor etc then it's just a very complex tarp or fly. TarpTents are, technically, tents by my definition. Most are single-walled, some are double-walled, and some are hybrid 1.5-walled, but they are tents nonetheless. I'm a bit conflicted on those old-timer A-frame tents that are made with flaps at the bottom to shovel dirt on to keep the critters and wind out. I guess that when used as-designed they are fully-enlcosed and thus tents.
Even a mid is a "pyramid tarp" according to most sources, if it lacks a floor. It's just a somewhat specialized one. And of course adding an inner net makes it indistinguishable from a tent, really, since it negates any weight saving while adding complexity and fiddliness, and is thus a net loss. If you want that then just get a tent to begin with- TarpTents are nice, and the Moment is a pretty decent 1P TarpTent. It only requires two tie-out points, so it's pretty easy to go without stakes at all and just use trees or rocks. A Moment is also one of the fastest shelters to erect- the second time I set mine up it took about 60 seconds flat.
Hammocks are probably different enough to deserve their own category, so we can probably divide all popular backpacking shelters into: tents, tarps, hammocks, and built structures like debris shelters and igloos. Warbonnet and Butt-In-A-Sling seem to have good reputations as hammock makers, but if this option interests you then you should check out hammockforums.net.
Regarding choosing between flat tarps, catenary tarps, mids, tarptents, 1-wall tents, 2-wall tents, hammocks, igloos, etc., I'll just say this:
They ALL have drawbacks and benefits. We can sit here and discuss/contrast them all day. But since this is BackPackingLIGHT I would propose that we're probably being asked about lightweight options. Heck, Big Sky makes some pretty impressive lightweight double-walled tents if that's what you're looking for, and I've heard that their logistical problems are a thing of the past, but they are expensive. I'd probably recommend a TarpTent first.
I've never had condensation problems in a bivy, but then I've mostly been out west where the humidity is tolerable, so YMMV. I can easily imagine condensation being a problem on the east coast. But I very specifically mentioned all-mesh bivies, just for keeping the bugs out. Hard to imagine much condensation in those. MLD makes one called the Bug Bivy- I'm sure that others make them as well. MLD will also custom make a Superlight with a much larger mesh window if you ask- mine is like this, to avoid the claustrophobic feel and for better ventilation.
Perhaps Tyler could give us some idea of his priorities? Can you rank these:
Simplicity/ease of use
Ah, wait, he did say that his priorities are weight/size and proof against rain. By size do you mean packed volume or do you mean footprint size?
For combining weight and rain-proofness I'll stick to my guns with the mid/bivy combo, but the footprint is large by some standards, as it is for the TrailStar. A decent TarpTent would be second choice, for me. For coastal rain I would avoid a small flat or catenary tarp, because wind direction can change and catch you off guard. (But then, lots of people are happy with their flat tarps...) Or, y'know, you could just use a bigger tarp but then why not get a mid for the same weight? And mids are DEFINITELY easier to pitch than any rig you've every seen for a flat or catenary tarp.