The idea sounds great. But this way cannot do much more than smoke tests. You can test if the kernel boots on the target's hardware. What you cannot really test is if btrfs will work on the user's drbd device which runs on top of LVM which runs on top of some special hardware RAID controller or such interesting setups. It's at least very difficult to test if suspend/resume works or if the user will experience some performance regression in his favourite game. You cannot test if the external display works automagically when the laptop is put into it's docking station.
In short: it would be a step forward but there's still plenty of stuff which users would have to test manually. But of course: the perfect is the enemy of the good.