I'm not sure if it is helpful to discuss combos I haven't tried out or made work yet, but anyway here goes. I have been wondering about two combos in the room where the Matuvu is located. The first one involves the Matuvu for 750 points, but taken at the same place where one usually gets it for 250 points. One can start with the gems on the Trampolines and work oneself up to the broken bridge by taking the gems on the ledge, fall down and get the three gems on the Mushrooms and continue with the two gems at the upper level before coming to the two gems on the broken bridge. One has 13 gems before the Matuvu. The good thing with this combo is that it is easy to get the Matuvu in combo, and one can continue the combo with the gems below, saving the red gems for last. The downside is, that it is horribly difficult to get from the two gems after the Mushroom to the first gem on the bridge. I have tried running and rolling many times, and a few times I was one nanosecond away from continuing the combo, but so far no luck. I grew tired of the many restarts and the long movie at the beginning of the part, so I have left it for later.
You have mentioned yourself the 1.000 points combo, which is the one I have succeeded with once. As for the 1.250 points combo, well, it is like the first combo above, I need just a few more nanoseconds to continue the combo from one group of yellow gems to another. And that is what I wanted to try out if it were indeed possible. I haven't made that work either. And furthermore, one has to use the third yellow gem on the wooden bridge near the entrance to combo the Matuvu with. I guess you use the first one on that bridge for your 750 points combo, right? Try to see if you can do it with the third one. It's beyond hell.
By the way, have you made a video of your 750 points combo?
And how big is your Fairy combo?