For many new players the game is already strange and new and overwhelming.
I'm not sure if this would be the best move.
If it were something more experienced players could unlock (like, by having at least one job at cap) in order to make things more engaging when level synched through ARR content... I'm not sure that would accomplish anything either. Spamming just a couple of buttons vs spamming them faster doesn't really change the fact that you're not doing anything involving.

Also, if they did give us any kind of buff like this wow ARR content would just melt. It's already easy as heck.

It's an interesting idea, but I don't think it having DPS hit 1 - 2 slightly faster would solve the problem of people not having a lot to weave with pre50.