ESF is not designed to save..
The point is to get stronger, fighting people in a game, using your skill to be the best. Its a multiplayer game based on your skill, not on your ability to rack up PL before even going online.
With ECX however your powerlevel does save....ECX is basically the latest rendition of EVM. Flooded with features that unbalance the multiplayer community tenfold, but it will do what your are asking.