TFT a few key issues
Lets start off by saying i actually really enjoy this mode. however there are some glaring balance issues.
First off way too many nobles are at the common rarity, which leads to most people flooding the early game with noble buff many with silvers at first pvp encounter. To resolve this i would suggest moving garen to at least uncommon rarity. he is an absolute unit and near unkillable with an early silver
Second is again nobles in addition to their being too many different nobles at low teirs there are just too many as a whole making is harder(not impossible) for other builds to even exist in the early/mid game as the champion pool is just flooded with nobles.
Third, one last time is nobles first class buff is too strong for how easy it is to obtain, early game it can turn even a bronze character into a nightmare with the right item in addition to nobles buff at first rank should only be applicable to nobles. make nobles fall in line with all other buff types
Fourth, Glacial is too easy to splash into any build at no expense, 2 glacials for a 20% stun chance on attack is too easy. make it in line with other 6 man buffs and be 3 and 6 glacials for 20% and 40%.
Fifth, Assassins are derpy and inconsistent at start of combat, if opponent is packed in the corner they dont jump at all or jump to front line, sometimes they jump to squishies in the front even when there is room to jump to tanks in the back. sometimes they just stand around for 5 seconds after jumping to the back as they process what is happening at the new location.
Sixth, Item drop Equalization. when fighting mobs at the end of the stage you should be assured at LEAST 1 item drop. extra drops are fine rng but getting nothing and then going into your next fight with an opponent who have 3-5 completed items while your sittting there with just a recurve bow from your starting champion.