As someone who does not currently have a hydraulic 3-point anything, I feel completely justified in answering this question as a complete novice.
I find that I adjust my top-link WAYYY more than I adjust my side-link. However, I do more mowing, box scraping, rototilling, etc, than I do grading my driveway (and it shows!). However, I do have a back blade, that when adjusted at an angle, the side link must also be adjusted for the correct positioning. Your mileage may vary. For me, I'd get both, the top and tilt, but if you only have one remote, then you are stuck with one or the other. Unless you wish to unhook the hydraulics from one, hook to the other, make your adjustment, rinse and repeat. But I think that would most certainly defeat the purpose of having hydraulic links. I'd look at possibly installing a second (and third while your there) hydraulic remotes on your machine.