Peelay said:. There's room for it to be tightened further but I don't think I could close the QR unless I used a pipe if I made it any tighter.
That really shouldn't be needed, there must be something else going on.
Quoted post said:The wheel moves after I've closed the QR
And you are absolutely positively sure that it's the axle that moves in the dropouts, or is there somewhere else where the move can occur?
Quoted post said:even before that I have trouble getting it perfectly centered before tightening it.
How did you check the rear triangle? Try standing the bike upside-down and stretch a string so that it lines up with both front and rear wheel. A buddy is really handy for this. Keep the string as close to hub level as possible without either frame or spokes disturbing the string. If everything is aligned correctly both "fore" and "aft" section of both rims should be on the same distance to the string.
If you have a wheel that isn't tracking properly, then aligning by the chainstays will force the QR to try to settle at an angle which can cause it to slip later on. To keep the rim at the right place in the frame you need to consider three issues: dish, locknut/spacer combo, and frame (mis)alignment. Ideally the rim should be centered between the locknuts while maintaining the correct amount of dish and the chainstays should be symmetrical. If the dish is wrong, if someone used the wrong set of spacers "inside" the locknuts, or if the frame is lopsided then you can only center the wheel between the chainstays by setting the axle at an angle. (unless you have faults that cancel each other out , of course)
Find a position where the wheel settles steadily (even if it's not tracking right). Note Rim/tire clearence and axle position. Now stick your wheel in "backwards" with the axle in the same position. If the rim isn't in the same spot then you have a dish or spacer problem. If the rim remains in the same spot then you have a lopsided frame.
Quoted post said:What are these far fetched options?
Well, if your locknuts aren't properly torqued and your bearing momentarily seizes, this can actually unscrew the hub and change the alignment of the wheel. It shouldn't be rideable afterwards though.