My suggestion: Take advantage of Shimano's great interchangeability between component lines. I'd switch the 53t outer chainring to a 49, lose the Ultegra rear derailleur and cassette, and substitute a 12-34 Deore XT cassette and Deeore XT long cage derailleur; you'll still have a good high gear and triple-like low gear, you will lose some fine differences between higher gear cogs but still have a lot of usable gears with a quieter, lower-maintianance drive train.