Here are some of my own rambling thoughts about the next-gen Roadster. . .
Will it even be a "roadster" in either name or form? That we got an open-top 2-seater the first time around seems almost as much a matter of circumstance as choice, since the Lotus Elise was the starting point. Could it go 2+2? Could it be designed from the start as a hard-top? Will it be a true, dedicated sports car or more of a high-performance pony car? One can imagine that the latter might reach a wider audience -- but some might see as impure and compromised.
It *should* be built on top of the Model 3 skateboard. That's just the sensible, efficient way to do it, and is the kind of thing the skateboard concept was originally intended for.
The skateboard layout, AWD (I presume), Supercharger access and economies of scale should combine to make it a much better-specified, more attractive and more cost-effective car than the Roadster. Cost-effective doesn't necessarily mean cheaper, though. It depends on how Tesla position it in the market. Personally, I hope they try to keep the price within the bounds of the original Roadster (if not a bit lower) rather than go for the "exclusive supercar" gold ring. Less Lamborghini, more Corvette. Teslavette?