Love it or hate(more) it, ranged cav is part of the game.
They'll probably lose the round, so why not let them get a few points to try to get valour? Should they not do that so you can save 1 death on top of getting +1 multi next round? Its not pleasant to be on the receiving end of, but the prerogative of ranged cav at all times is to incur damage to enemies from a distance, whilst taking non themselves. The flags, and few remaining players, just means they focus their attention to fewer players, potentially who cannot counter them.
I dunno man, its shit when it happens to you, but the multi makes it ok for me.