Motor choice for 2wd= fast, or slower + boost

[Timee80]

I run a 10.5t in my 2wd and i love it. I can use more of the throttle more of the time and its much easier to drive and make use of available traction. The motor i have in it is just a cheap speed passion sportsman at the minute and lacks a little bit of grunt
Should i buy a better 10.5t and simply up the turbo timing on larger tracks, or should i just get a 7.5 / 8.5?
Not long ago everyone was running 5.5 / 6.5 in 2wd and now the norm seems to be 7.5 / 8.5
Will people start to move to the even slower motors now that the new breed of esc's can deliver the dynamic timing that can make motors crazy fast?
Whats your thoughts?