Seeing ive exploded more clutches than most here(12? 1st gears), Ill definitely agree with 1st gear is only needed. Ive kept most of the exploded ones and yes around the pins, but usually because a35's(and same design on 55's) have only 1MM cross section where they shear off from force. The a3's design is literally double at 2mm and last with real clutch material(light mods needed) They are still only CAST(failure) aluminum.
Some designers in Europe have redesigned the bell but i feel it very unnecessary, and would add lots of cost(and weight) Yes i have killed one before, but only because the clutch came apart and hurled into the bell in a very non-concentric manner.
I keep usually 2 extra sets of kevlar lined 1st gear setups most of the time(second gear doesn't even need that)and strong springs 15-20lbs depending on fluid and how much power i am setting them up for. I also have stock ones and a crank with bell if you need for the setup and tooling. The splines aren't weak at all, ive seen a few failures, always are due to people not using the correct washers and lack of thread locker, and loose to ruin the splines.
PM me for info