No need to drive between these two cities unless you intend to see
/visit towns that once were part of the Sudetenland before proceeding
to Prague.
And what about the Spreewald, the park of Bad Muskau, Görlitz, Bautzen, Saxon Switzerland, Freiberg, Meissen, Saxon Switzerland, Seiffen, Oybin and the Zittau Mountain, Litomerice and Bohemian Paradise?
The towns of the Sudetenland along the route on the other hand are mostly pretty ugly (Liberec, Usti, Jablonec, Decin).
You can easily spend a week or two between Berlin and Prague, and the car gives you the opportunity to see places only Europeans visit. It's very nice for example to drive from Saxon Switzerland via Bohemian Switzerland to the Zittau mountains, and from there via the Lusatian mountains and Bohemian Paradise to Prague.