Like kitru said earlier,, and it have been suggesed in other threads too. Make all bosses needed for the FP to complete. Or you could increase agrorange on mobs in FP´s. That would reduce the skipping of trash alot too.
I know, lots of people would complaint about not being able to skip, but the complaint would probably be from the same people who barely run any FP anymore, and when the do they do it for BH coms that they most likely only would need for an alt or a companon.
Why should EVERYONE be punished because of a few QQers on the forums .. you CANNOT force people into doing complete runs. If you really want to kill everything - setup your own groups.
Btw I run random t1s pretty much every day on my BiS 63 main .. why on earth would I want to waste time on bosses which drop tionese crystals ( of which i am already capped ) or outdated gear ( worse then the free recruit stuff we are getting ).
Also finding new ways to skip stuff can be pretty fun