Why Vel'Koz over other champions?

Why would you choose him as one of the "big six" when his biggest issue, according to you, is "distinctiveness", something that can be fixed in better ways than a semi-rework? He's a floating purple eye monster thats a total meme with him being a knowledge-whore and his ultimate/Q are EXTREMLEY iconic and unique. His other abilities are fine and tie in to his theme well. I see no problem. Even if he IS missing something that I'm not seeing, the only changes he needs should come from a patch, not a semi-rework, and given the fact that he's really balanced I see no reason to include him on the list over other champs that are more problematic. comes to mind when I think "lack of distinctiveness". The only unique thing is her ultimate; everything else is basic, like her boring passive, basic Q blast, basic shield, etc. Even though she already had a rework and it fixed some of her problems, it stripped her of her identity besides her ultimate. Why choose vel'koz over champs like and that have super similar playstyles? Why choose him over champs like that have seen low playrates/have awkward abilities and passives/are be stupidly op in the right situations?