Thank you all for the excellent discussion about these compromises.
My benchmark for a large but still readily trailerable tri is the Dragonfly 28 as its outriggers stay in plane (in contrast to the F tris)
With the HP "we are still stuck with stooped headroom saloon" in these sizes. If you cannot beat them, join them: why not shift the ww hull more to the center of the saloon and have layouts like the front halves of the central hulls of tris, butted against each other. The German Sol had already such an overhang to ww. Just double that and profit from the head room of the hull for moving about from one end to the other. One can still have a head/shower at each end. RM would drop some compared to the classic HP ww hull, but deck clearance would gain.
The exhil 40 folding beams are much like a double swingwing. To become trailerable the "swingwings" need to be able to come closer together than now with the 10' foot folded beam of the current exhil 40.
But then the rudder needs to be out of the way somehow ... I am looking forward to Rob/Steinar's solution to the trailerabilty puzzle.