i had this problem with my 39g pro when i tried to install the eheim 1262. it was just too much flow for the durso. you can try and restrict the size of the hole at the top of the durso so the drain can accommodate more flow without having to "fill and flush," but i'll tell you that i was not able to fix that problem, even when i tried to use a ball valve to slow flow from the return pump. i switched to the tunze 1073.020 return pump and I have been very happy with that. no more fill-and-flush problems (no noise whatsoever in fact). I've heard good things about the 1073.040 as well.
using the valve on the drain is a fine way of fixing it (gate is easier to fine tune than ball, as you said); however, you can get yourself in trouble in a hurry if something clogs that drain since you have no "emergency backup" like a typical "full siphon" gate-valve controlled herbie-style drain would have. it will quickly overflow your display if the drain gets clogged.
here's a solution if you don't want to replace your return pump: you could always re-purpose your return bulkhead as an emergency drain and run the return hose outside and up-and-over the back of the tank.
