Uh, let me put it this way... from what I hear, there are plenty of people in bronze 4 who would love to see Kael on every opposing team, because right now they only see stronger champions. For arena specifically, Kael isn't better than Elhain - if you're losing to teams with Kael, you'd also lose to them if they had Elhain in Kael's stead and with his gear. The reason you're losing is most likely your speed still isn't high enough - or indeed you don't have good enough gear on Elhain yet. 

To be clear, when you talk about 'two critdam blues', you mean gloves with crit damage as main stat? Or you mean any piece from the crit damage set? Sets are only of secondary importance, stats are what matters - the bonus you get from a crit damage set is peanuts compared to what you can get from crit damage main stat gloves, or even from a crit damage amulet. Though at your level of progress, it may be tough to get enough crit rate if you don't use crit rate gloves, rather than crit damage ones. 

This aspect of the game is not so much built for whales as it's built for veteran players, whether whale or f2p, who've played long enough to have farmed and leveled good gear, have pulled some good champions, have built their great hall, etc. New players find it very hard to progress in arena, even if they're whales - because you can spend a lot of money for basically no result, if you're unlucky. 

And yeah, this definitely isn't a role playing game - you can kinda tell from the way the story covers about one hour of playtime, if that...  

Kael isnt your issue - really. His multiplier is a bit higher than elhains but not dramatically

On the topic of critical hits, its quite hard to get crit rate to 100% without using crit rate gloves.

For now just use crit rate gloves in my opinion. When you have gear with crit rate rolls on them then you can use crit damage gloves

Anyway the issue isnt just whales. Whales often have a better roster, but they still wont succeed without gear, and that will come from either grinding to hell like everyone else- or whaling out even more by buying the gear packs. Basically gear is at least as important as champs.

I completely sympathise, arena is a mess - but honestly it isnt anything to do with kael.

Honestly Kael isn't that strong. I beat this team:

Kael lvl 60 

Scyl of Drakes lvl 50 

Kael lvl 50

Madame Serris lvl 45

With this team:

Samar Gemcursed lvl 50

Galek lvl 50

Jizoh lvl 44

Gerhard the Stone lvl 40

There is absolutely no logic in "I can't gear my Elhain in critdam" and "I can't beat Kael because he is so overpowered".

The right conclusion would have been, that you can't beat all that Kael teams because you don't have the right damage equipment on your Elhain. Do you think anything would change if you use Kael in the same equip instead?