Is it possible to put the spout and levers on to the half wall of the shower? Maybe you could build it up enough to have them coming out of the wall directly over the tub. Not sure where your plumbing access is though and if drain is on other end maybe you could mount them on that wall?

I'd try to learn to live with it instead of buying a new one. Are you completely convinced it's a safety issue, or is that influenced by the fact that you're unhappy it's not in the right place? I've had remodels where a few things weren't done right and it seemed a big deal at the time...later I didn't notice it.

Re: setting it offset, etc.: Pay close attention to what you currently do. I thought I'd put handles and stuff on the left, since I'm right handed, and though I'd be holding my pans, etc., in my right hand. But I find that I *hold* things in my left hand, which leaves my dominant hand *free* to pick up the sponge, turn on the water, etc. I even prefer my soap dispenser on the right, bcs I pick up the sponge w/ my right hand, and hold it under the dispenser, and push w/ my thumb--one handed--all while holding the dish/pot in my left hand. Also, i think that if you have a window over the sink instead of a cabinet, you may find that you'll adjust to that extra height more easily and rapidly than you think. if it's just aesthetics, don't give up the functionality of a center faucet for that. Bcs the off-center could look just as odd as a huge faucet in the center. Will your faucet reach most areas of the sink from the corner?

The rule is what is convenient for you.