Its not even a good idea. Players play better when they're amongst their peers. Having a rag tag group of random guilds trying to kill buffed VP? Probably isn't going to happen. People that have been raiding together, and know their strength/weaknesses is a far better solution, even if it takes a week longer.Which makes the server progress sooner? Sharing the first kill or waiting till a solo force has keyed up?
It's not brain surgery. Heck, you expressed yourself the worry of how long keying for VP may take and the impact on progression speed. You already see the problem, just have too much hubris to accept a possible solution.
[Although if they speed up Trak from the get-go/very early on it'll be moot anyhow - as would if you could guarantee 100% of FFA kills if there's a FFA timeframe - but again the latter requires hubris again, considering it's a timeframe when people will care to compete more for FFA]
Swear man, these fucking rotations lol.