When playing as Yuumi, you start with an initial point in W. That's honestly great for an ability so important to her kit and allows her to unlock her full power not at level 3, but at level 2.
However, the first skill point seems to mess with the maxing order on Yuumi. For those not familiar with the rules for skill point distribution (aka when are you allowed to skill which ability), the rules are the following:
> A basic ability rank can not be higher than the other two basic ability ranks combined plus 1.
So, on Level 1 you can skill one ability. This is allowed because 1 (the new rank) is equal to (but not larger than) 0 + 0 + 1.
On Level 2, you can skill another ability (but not the same one again) because 2 is larger than 0 + 0 + 1.
On Level 3, you can either unlock your last ability or rank up one of your other two abilities. Because 2 = 1 + 0 + 1 which is still allowed.
With Yuumi however, things are different.
Because you already start with a point in W, you need to choose Q or E on Level 1. For this report, assume it's Q.
On Level 2, you should be able to choose any ability, right? Learn the last one or level up W or Q to rank 2. That's basically level 3 of what I described above, just earlier. **WRONG!**
For some reason, the game forces you to take E. You can not rank up Q or W while you still have E unskilled at level 2.
Now, that's strange, but I can get behind it (kinda). You can get around it by not using your skill point at level 2, then at level 3 you are once again allowed to skill anything - why? If you do that, you still have a skill point left, which once again the game forces you to use on E. So you gained nothing and could have just taken E at Level 2. When you have skilled all your abilities, it works as intended as far as I can tell.
In any case, this seems unexpected and inconsistent with rules previously laid out which apply to every champion.
I would expect it to be less restrictive, i.e. not forcing someone to take Q and E on Levels 1 and 2. Leveling up an abilty twice by leaving the last one unlearned is possible with every other champion, why not with Yuumi?
TL;DR: Leveling up abilities with Yuumi feels weird because you are forced to take E and Q on the first two levels. I would expect it to be like any other champion, just at an earlier level: Yuumi should be able to have the same skill distribution as a champion one level ahead of her (due to her bonus point in W.) This is currently not the case.