There have been several suggestions for game modes that would utilize the existing maps and merely require changing the win conditions. I'd like to see Team Deathmatch and also maps that are currently Capture/Defend changed to Capture & Hold with neutral capture points with a set timer/score limit.
Love or hate battlefield - conquest is a good game mode. I'd love to see conquest assault be reborn in 40k, seeing as dice have fallen out of love with that version of conquest
They don't even do that in their oan game though! Also they'd just complain about the lack of the support classes warding! Damnit painboy where's your sightstone!?