Back to the idea of using trampoline frame(s) for structural support. I've attached some images to help illustrate this idea. The notches in the rafters that would accept the tubular steel are angled backward&up, this would work with the compression forces to prevent the steel tube from falling out. also there is only a 4'' space between each rafter @ the toono.
the drawing would be using 3 tramp poles. a 12 footer a 14 footer and a 15 footer.
specs for sears trampoline
18 gauge galvanized steel that is 1.5'' diameter
Tramps are usually rated for 1000lb on the net (jumpers up to 200lbs) im pretty sure you could have a few thousand pounds on a trampoline net before the frame would give out
I think this would certainly weaken the wood, having notches, especially three of them. I've seen people burn holes in a toono ring made of wood for each rafter (more traditional style) I was wondering if burning the material away helps to keep the structural integrity of the wood.
another thing to consider is lightening. have large metal rings at the top of a tall (16ft tall) yurt could attract lightening. I think you could ground them with a nice heavy gauge wire. or coat them in a PlastiDip coating.
Plastidip coating which is a rubberized spray on paint use on cars. I think could be safe for interior living areas. would'nt be terribly expensive and comes in many colors.
Im pretty sure LVL are going to be out of my budget. I found a company that does offer them
House Framing Lumber and Studs, Pricing
they have LVL of many sizes. priced per linear foot.
Closest thing they have to a 2x6 is a 1.75"x7.25" @ 3.33 lnFt making a 16ft unit $53.28! yikes. 72 pieces => $3836.00 wooooowzers!