Two things are missing in flying a sim, any sim atm... that of the "flying by the seat of the pants" and accurate depth perception.
hardware wise, its in the quality of stick being used, bearing in mind most desktop sticks are way shorter than their rl counterpart,... meaning a small movement on the dt stick equals a largish movement on a long in sim stick. So , what you do, is just learn to use to guide the stick using only your finger tips (the MS FB stick was great for this)
You need to learn how to trim for level flight properly (this involves throttle setting and flap setting, for getting it right), with the refuel flap open before getting anywhere near the refueller.
Nice and gentle will get you a lot further than trying to adjust for the gyrations, when on connection... the hard part is getting it into the slot first