Small groups in PVE right now are entirely possible, and can be done with relative ease. However, as my 3 man group has encountered, the time limit on smaller man missions is BRUTAL. It is so hard to complete the mission with time limits, as they don't adjust well with smaller groups. It'd be nice to have the timers removed as a whole, but I can see why the devs have them. So if anything, please adjust either the timers or the capture rates for game modes with lower amounts of players.