i love your work here. i think it is in the top 3 best trys, maybe the best. i cant tell you how many hours i spent on this and how many emails and experiments i had. also did comparison rides between my cb's for seat angle analysis. i cut seats, i used hinges, i used foam, i did all kinds of stuff. i had a few good versions, but, even on my longest rides and tours, i came to a few conclusions:
1. the single greatest comprimise bike and seat angle is found on the s30. a modern version of this bike should still be made. they are unicorns and for good reason. the best seat angle and break down for shipping the best. i still dont have one, but my neighbor does.
2. the single cheapest lighest and easiest mod to use is a foam wedge. i was delighted when cb started to sell one. i have an entire box of my experimental wedges.
3. all things considered, ultimatly i prefer the thor seat. i have them on the 20 and 40 i ride the most. i still have standard seats with foam on my other 20's and 40's but even with the thor i have a foam insert. recently bought two more thors to test an idea....
4. gearing is more important than seat angle. i have spent even more time on gearing and driveline.
5. i have ridden many multiday rides on the 20 and the 40. the longer the days the more i prefer the 20 as i get recumbutt on the 40 around 100. the steeper the climbs the more i prefer the 40, so i can push on my back. i have experienced wheels slip on both so bad i had to walk the bikes. nowadays i just dont go on those rides any more. i hate climbing no matter the bike, so, if i am going to be on the steepest climbs, now i just bring frankentrike. it is geared to climb, and if i get exhausted, because it is a fwd mbb trike, i just stop and rest, then i start up again. the seat angle on it is lower than a 20 with a little kick up at the shoulders.