The only issue with BLU is the missle spell being able to take 75% of a boss in 3 seconds. If they only use their normal kit you still get some hits in, enough to get silver, most of the times still gold. Of course day 1 it was more BLU zergs killing everything, but you just had to avoid day 1 and by now it is fine. Except people still killing bosses in under 10s with missle, something is wrong if you think that is ok or fun.