From my experience for goat and sheep hunting, you typically aren't in heavy buggy areas for the duration of the hunt. An exception might be the very beginning or very end of the hunt when you're at lower elevations or moving through different drainages. Bugs haven't been a major issue for me during my sheep hunts. I will add that I've noticed with the HMG Ultamid tents (or any tipi style), that what bugs do enter are automatically funneled to the top cone of the tent and just kind of bounce around and congregate up there. It's easy to unzip the door and swat them out. If you're concerned about bugs I do know some of the tipi style tent manufacturers offer a mesh inner portion (HMG offers several). I haven't used them though, as I don't see the need. If I'm going to hunt an area that is known to be buggy, say for other species or other terrain, I'll take one of my Hillebergs. Once you add the weight of the mesh inner, a groundcloth or bivvy, and the floorless tent itself, you are probably closing in on the weight of some of the fully enclosed tents you've mentioned above. If it was a later season hunt, or a more coastal region (like goat hunting) I'm probably grabbing a Hilleberg though.
The tipi style tents might take a little more time and care to set-up. I would bring at least 4 of the MSR Groundhog cyclone tent stakes for each corner. You can place rocks on top of the stakes to secure it, and I typically use all the guyout points. I also bring a groudcloth to lay under my sleeping pad, and use my rain pants, gaiters, and glassing butt pad to lay down to create a covered space around my sleeping area. You have to be more mindful of where you might pitch a floorless tent too, to consider where water is going to go during a sustained downpour. You won't have as much margin for error if you select a poor campsite to pitch it, compared to an enclosed tent with a bathtub floor.
The red label Hillebergs (such as the Nallo) are also (obviously) warmer than any floorless tent without a stove. Another underrated feature of the Hillebergs (and I think the Kuiu's?) is the ability to quickly pitch it in a downpour with the rainfly already connected and on the outside. This way the inner portion won't get wet. There are certainly pros and cons to each type; but the weight savings, larger footprint, and less bulk of a floorless dyneema/CF tipi tent are undeniable.
