Tarks, the animation may have been better if Cosgrove Hall had done it, but the scriptwriting would definitely have been better, especially if Brian Trueman had been involved. It was the writing wot made DM, the animation was rudimentary, at best, with many of the crew having taught themselves, from books!
I was one of the first "trained" animators to work on DM, and my animation course only existed as part of a graphic design course which set up its animation facility the year before I joined. On top of that, it had almost no equipment, so you can see those were very early days in British TV animation.