It seems almost too obvious to say that the best model, if cost, size, performance, etc are no longer limiting factors, is to run code in both client and server

It seems almost too obvious to say that the best model, if cost, size, performance, etc are no longer limiting factors, is to run code in both client and server. Advantages of server: no need to distribute code, and data naturally more consistent. Advantages of client: offline accessibility, speed of light limitation on performance. Of course, in the real world, you have additional tradeoffs, but those I described are probably timeless and universal rules.