The problem I have now is that I'm *really* tired of D2L. As you point out, it's really tough to get any features added, and the interface really hasn't evolved at all. But the guy who administers D2L at my college loves it and doesn't want to change. I met with him recently and he said something about putting his foot down with D2L "and this time they're going to listen!" I thought, Good luck with that.
I was a student this year in a Canvas-run course and also was paid to teach a D2L course as well.
In the 14 years I've been using Moodle I love it more and more.., but IMHO the single most glaring issue is Moodle's really primitive way of grading forum posts. I use forums all of the time, and other than quiz and assignment, forum is the most used feature of the website.
In D2L, you can assign a forum as an assignment. When you grade the forum posts, you get a list of students. On each student, you automatically get a list all of their forum posts for that particular forum assignment. You can then post feedback and give a grade.
In Moodle, it's a mess. You have to assign a rating by clicking the user post. It's not super easy to just bring up all of the posts by one student because you have to hunt around for them. There is no button called GRADE ALL POSTS. For students who haven't posted, you have to then go into the grade book and type in zeros for those students. It's a huge headache.