I saw that Rek' sai was mentioned in one of the previous gemaplay updates and I wanted to express my thoughts on the champion currently. Rek' sai has been pretty underwhelming for almost the entire season, and I feel that she needs to be reverted so that she is played as a full tank. Currently she is the worst champion in the game after 15 minutes. A former LCS analyst agrees with me on that point. She has the same pitfalls as Rengar before his initial rework, being that she is a squishy champion that has to dive into a team and will either trade a kill or simply die. Rek' sai is even worse than old Rengar because she cant simply instakill a squishy target, due to the fact that she has to first knock the squishy up, Q-AA-AA in order to get full rage and then E for the true damage. Most of the time this isn't even enough to kill a squishy, whereas old Rengar could simply triple Q and instakill.
Furthermore, Rek' sai's ultimate is one of the worst abilities in the game. This is due to the fact that it is so telegraphed; everyone can see the animation begin, and the animation is quite long. Additionally, her ultimate can be dodged by every single champion in the game because essentially everyone takes flash. Champions with a dash such as Lucian or Graves can also avoid her ultimate simply by dashing away. Her ultimate does a good amount of damage, but it's simply not enough to make up for how bad the rest of it is. Also, if a champion survives your ultimate, it is very difficult to continue chasing them down with autos because of the animation of the leap. This is one of my biggest problems with this champion. She feels clunky to play in that regard.
Rek' sai is also very immune to CC, which isn't a problem only she faces, but when built damage oriented, she gets blown up before she can do anything.
Another glaring problem with Rek' sai is her W. Her W is very bad currently, much worse than it was before her rework. The knock-up only affecting one target is pretty bad, considering most champions can simply just kite away from her. Another obvious problem with her W is that it does not prioritize champions. This leads to situations where an enemy can simply run into a minion wave to avoid being knocked-up, which makes Rek' sai's ganks useless. This would be solved by reverting her so that the W can knock-up multiple champions, with the knock-up duration dependent on how close Rek' sai is to the enemy champion.
Additionally, her passive healing is pretty much negligible; when clearing with her you still get relatively low.
Reverting her to her previous form would fix all of these issues. When built as tank, she could dive into a fight and knock up multiple champions. She still has no escape, but she is meant to soak up damage so this is not an issue. As tank, she can also face-check without dying instantly. If reverted, she could also get multiple knock-ups off in a single team-fight, due to the fact that she would be tankier and her per-target knock-up CD would be lower. As a said before, current Rek' sai is completely useless in team-fights because enemy champions can simply walk away from her to avoid the knock-up. Tarzaned recently released a tier list video and he placed her in the lowest or next to lowest tier. Valkrin also expressed that Rek' sai is an awful champion. I haven't exactly kept up on pro play this season, but I don't think she has been picked at all, and typically only good champions are picked in pro play. It would make sense for her to receive the Rengar/ Leblanc treatment.
Rek' sai is a bruiser with assassin scaling. Her passive, W, and ultimate are very bad abilities with glaring problems that have yet to be addressed. Even after her recent buffs in patch 8.14, she is still one of the worst junglers in the game at all levels of play. Rek' sai needs to recieve the Rengar/ Leblanc treatment.