There are unofficial plans to build a Roadster 2 as a Porsche 911 type of car. It's being discussed here as the next-gen Roadster, and expected to follow soon after the Model E (Gen.III $30k - $35k car). The Model E, which is more in that price range, is however expected to have 4 doors (a smaller Model S), although that is a subject of discussion. However many expect Tesla to build Coupe versions sooner or later. However even the initial 4-door Model E will probably have very good performance.