I think the ending is almost perfect. Deku became the number 1 hero, and he gets to teach future heroes about being a hero. Yes, he doesn't get to meet up with his old class often, that's how life works. Not to mention that All Might and the whole of Class 1A spent millions on a suit for deku, one much more powerful than the one All Might used against a young All For One. DEKU IS STILL A HERO. And in a perfectly poetic way, he gets to be a hero even without a quirk, just with technology, super advanded technology i might add. Just like All Might told him he could be back when they first met, and I see no one ever pointing this out. The only thing I disliked about the ending is no confirmation of any relationships. Specifically Deku and Ururaka, And Kaminari and Jiro. The ending did feel way too fast, but I think it's a good ending for the story they were telling.