UMM bastard swords are better than a falcata. The D10 compared to the D8 is actually pretty big. By the time you get a crit the extra 1-2 points of damage per hit makes up for the smaller crit multiplier.
This is for 100 attacks, I use max damage and improved crit here but it scales exactly the same if you use average and no imp crit.
BASTARD 10 max damage, 20% crit change, 800 non-crit damage, 2X crit mult, 400 crit damge, total damage 1200
FACATA 8 max damage, 20% crit chance, 640 non-crit damge, 3X crit mult, 480 crit damge, total damage 1120
if my math is right, this would make the bastard sword the best 1 handed weapon (had this in excel but it doesnt format properly)