Flying a Falke and flying a glider are chalk & cheese. Gliders are so much nicer to fly. Circuits in a Falke might be appropriate for someone struggling to land, but that's it in my view.
I would say more like different kinds of cheese. The Motorfalke is ugly and is low performance, but with the engine off, it does fly like a glider and more importantly has spoilers, so I was able to teach students how to make glider approaches. The key factor was repetition of six or so circuits, one after the other, which made for much better skill development. You also only need two people, the instructor and student, to have an operation.
My gliding club, which I have recently rejoined after an extended absence overseas, runs an aerotow-only operation, four days a week on its own grass field. Two tow planes, enthusiastic instructors and a club fleet consisting of ASK-21 and DG-1000 two-seaters plus a DG-303 and a Jantar.
At the recent AGM, I was staggered to learn that about 40% of new members don't rejoin for a second season. This is being investigated by the executive, but I suspect that the primary reason is that too much time is wasted hanging around the airfield waiting to fly. It's not the money - many people have the approximately £1000 it would cost a student to fly during the six-month season and it's cheaper than golf.
Coincidentally, I have just (finally) read Derek Pigott's autobiography:
"Delta Papa - a Life of Flying". A great read and in the last chapter, where he describes a typical day at Lasham when he was CFI, the use of motorgliders for training features very prominently. He puts the case for using motorgliders much more eloquently than I ever could.