I don't mind the little OBR... I would use much more if it were easier to 'unlock'... It really is like a brit mortar pit but better (not really a fan of mortars in general, though I always have *some*). Voted to keep (with adjustments).
A favored tactic of mine (against AI at least) is to build up a strong point around an Outpost (for re-enforcing), An MG nest out on each 'flank' (of the position anyway, with fire-arcs overlapping). Put an OBR near the Outpost at the center of the position, put sandbag walls between everything, and then park the medic truck behind the whole lot (but close enough to heal emplacement crews). I'll occasionally put an Arty fire-base back a little further again, but that depends on the location...
I use this tactic to create 'access denial' zones to hold important areas of the map without having to dedicate infantry and/or tanks to it, freeing up that stuff to flank the enemy, raid their positions/base, etc...
~JD