This is something which I think is pretty basic and surely Warmoth could do commonly. Just put, as a standard option, whether you want a neck to have the square Tele or rounded Strat heel shapes. They'll already do odd routings on the bodies (Tele neck pocket on a Strat, Strat neck pocket on a tele etc), why not apply the same to necks too? What if someone currently has a Strat body with it's usual Strat neck pocket, but they fancy sticking a Tele neck on it? What if someone has an existing Tele body with the usual Tele pocket but they want to stick a Strat neck on it like some of the Custom and Deluxe models have? Sure, Strat necks will fit into the Tele pocket anyway, but then you've got obvious gaps and that still doesn't help if you wanted a Tele neck on a non-Tele body. I can't imagine it's that complicated to do, especially with angled headstocks where surely it's pretty much just a case of sticking a different headstock on than you'd normally use.