Some ideas for Riot to buff these champions

Dear Rito, I have found that during gaming, Nunu and Olaf are kinda useless in the team fight or even anything they are on. Like Nunu's ult is not really helpful as he just has only slow, and Olaf has only his Q to slow the enemies, hard to approach them as they keep the distance and kite. So I'd like these ideas to Riot to buff thêm a little bit. Btw, they are 2 of the top champions who have lowest win rate. About Olaf , I'd like his ult to gain a bit speed and half of that for all allies within 1200 range. About Nunu , his E now does not slow at first, but will mark on the victim a mark for 8s. Within that 8s, every basic attack by Nunu or his allies on the marked enemy will stack the mark by 1 mark per hit. At 5 marks, next basic atk will detonate the marks and stun the enemy by 0.5s-2s. (The skillshots that deal on hit effect like Ez'Q or fiora's Q are counted to mark as well). R - Same as usual, but within the effected area, all enemies will be rooted 0.5s-1.5s for first time they get affected (Like Wukong's ult). Passive - Nunu gains 100% bonus mana regen 2s out of combat. I just want them to do more than being a statue in teamfight, Nunu will be more like a supporter than fighter. If you agree with these, test them on PBE and nerf a little bit if they were too OP.