There are speedrun categories for Any%, Glitchless and Best Ending, but not the combination of Glitchless and Best Ending that I am thinking of trying for this game. This would be a step trickier for me to record than I've done so far, and it would be a while before I could actually pull off a worthwhile speedrun of this, but I thought I would introduce this idea now. If implemented, I could see a few speedruns in this kind of category for my viewing pleasure and study!
Glitchless Best Ending wouldn't be the most appealing category to add, in my opinion, mostly due to the potential length. As it is, this game already has plenty of categories, and a couple of them have almost no runs.
If you want to do such a run, you can still submit it to the Best Ending category. g0go's first world record run of Best Ending back in the day didn't use any in-level glitches, but it was nevertheless submitted to the Best Ending category, which contained two other runs with extra glitches. At this point it's probably not possible to get that world record without using glitches, but the purpose of adding categories is typically adding new challenges or goals for a variety of runners, not giving one or two people a free WR.
I'm not a mod; this is just my two cents. If you want to convince someone to add the category, it's best if you do a recorded run first so that the board isn't in limbo.
Anything from me would be a while in the future. I understand that it takes some actual runners interested to get it to happen. I just thought I would throw the idea out there. Yes, it is a long run, but at least I found people responding right away here and on Discord! Thanks for the feedback.