Workaround: Don't like your character? Ask your GM to play another!

[Endarire]

There have been many balance threads about character classes, builds, etc. People have tried very hard for very long to fix a variety of things for more people than themselves.

Rather than trying to rework the system even more, talk with your GM. If you don't like the character you're playing right now, talk with your GM. It doesn't rebalance anything for anyone else's table or campaign (but may change your current campaign's dynamics and balance due to the new character). The end result seems more likely to get you the result that you wanted - a character that you more wanted to play in this circumstance.

Plot-wise, work with your GM to get something that seems fitting. Maybe your old character retired or exploded or was identity-swapped with another. Maybe it doesn't matter just so you can play the game.

[GilesTheCleric]

This is a good solution.

Some ways to do it in-game with RAW include using the Gates of Dawn/ Necrotic Cradle, Reincarnate, or even the Leadership feat if your GM doesn't want to have to introduce a whole new character. Gates of Dawn and Reincarnate can provide plenty of interesting RP.

[vasilidor]

I have done this. both as the DM giving the ok for the swap and as a player wanting to swap. some methods i have seen used/done myself include: magic bubble, you were always there as far as anyone could remember; you were that guy we just rescued, welcome to the party; previous character died - enter the vengeful relative.