I have picked up a bec with my archer (who has no skill in polearms) while naked scavenging on siege, and got 'bout 6 kills before dying to ranged.
I have an alt for all the weapon types and the easiest to use is polearms, but only because of polestun. The bec is overused and i see it in 99% of my matches, so i think people have a problem with polearms in general, its just that the bec is used so often that many people believe that the bec is overpowered, as opposed to just polearms with their polestun (which is really the only problem with them). If the bec really needs a nerf, just change it from pierce to blunt damage but without knockdown.
I have noticed the thing with bec swinging around blocks, but I have noticed it with picks as well and its not much of a problem, just mildly annoying.
Its 100 reach as Polearm gets -20 reach cos of Animation so its shorter than alot of 1 handers.
Not that many actually, only 7 are longer, the practice sword, shashka, long/knightly arming sword, arabian cavalry sword, nordic champion sword and long espada are longer than 100 length and the longest has a length of 105, not much longer.