You aren't limited to 2048x2048, that was just a limitation of old graphics cards. For example I'm using 1360x768 for Overlay and 2720x1536 for Background. Ideally you should set Background to 2x Overlay for the best image quality.
My one wish that SE make it so I don't have to carry around 8 different staves for 1 job. BLM could get a staff that has the MAB and INT on it that would effect all spells instead of just one element. SMN has Behamut's staff but if you want the -5 perp cost you need 8 more. Why not just give us One staff for each job? Could make it a Magian Trail staff not to easy to get done. But yea... this would be my one wish. :)