There is 1 unfavorable matchup - Metaphys. But you don't see many Metaphys users around.
If you want a strong and consistent deck then go for Six Samurai. I never regret spending all gems on it. If you think that this deck is unfair, don't complain, just build one for yourself to gain the unfairness.
The thing with the Final battle is that sometimes I may not see it during my first five turns. And when I finally draw this card, all my resources and monsters are over..
And in the next duel, I can have 3 Final battles in my starting hand along with Canadia.
This deck has no search engine like 6 sams