Kura is top tier for sure ^^
I would say Talim is still mid- at best, and that just like Omega with Zasalamel, Kura showed us it was still possible to do well with a weaker character if you're willing and capable to put in the extra effort/skill. Lots of things such as good defense, mind game, ability to read your opponents are not character dependent.
This is good, but in the end they didn't win the tournaments.
Now imagine these incredible players using a stronger character such as Kilik, Ivy, Voldo, Amy or Cass. Would they have wiped out competition instead of being very close to other top players using top characters ? While nobody can say for sure, it makes sense doesn't it ?