A straight chain is pretty much a non-starter, because the gear ratio will be too tall to be generally useful. If that were a good idea, they would have come that way from the factory, as it would be cheaper to build them without a jackshaft assembly. Your acceleration will end up being very poor, and you’ll be frying clutches on the regular, but yeah, once you finally build up some momentum, it’ll gain top speed.
A TC will be way better, and I’d probably combine that with a bigger rear sprocket.