I'm pretty sure all polearms (with very few exceptions) will be 2 slots at least, no matter if they are visible or not when sheathed.
I think there will be a couple of them 1 slotted, like the Shortened Spear, which makes sense. Only low tier ones of course.
About the archery, if warbow/lo(l)ngbow get 2 sloted, you'll be seeing even more camping archer on public servers, since no long distance archer carries only a stack in order to be able to have a melee defense of a 1hander. And those who start using strong bow's and lower tier ones, will carry 2 stacks of arrows and 1handers with them, and there are OP 1handers as-well.
With my archer atm, I only use LHSM when I don't have enough PS in my build to use a cutting weapon, which is the current case, only 4 PS. And no, don't think it's nonsense to spend points in PS and ATH in a ranged character. Ranged without any melee abilities and skill, is usually a dead ranged.
Cheers.
