To be honest, I had quite little issues with archers in game so far - either took them out with my own bow, or charged them while covering myself behind trees etc.
Some notes - polearms are sexy, and strong as fuck - but they are really, really hard to keep close, as you can´t store it in invetory, so you have to carry it in your hands all the time. I eventually always lost my polearms because I forgot where did I put it So they are like locally placed superweapons and quite rare resource. (Like BFG :D)
Shield + axe is probably the most versatile equipment, but its offensively quite average.
The reason is that with shield equipped you need more stamina for single swing, essentially limiting your offensive potential - and this is paired with fact that while axes have two not that bad damage stats (slash and blunt), they are always lower then damage stats of other weapon with corresponding quality.
So essentially - shield+axe is combo which always works atleast partially, but you will be much more effective if you equip yourself for the occassion - long sword against low-armor opponents, mace and shield (or maybe warhammer if they are actually ingame) against armored opponents.
Its of course up to you, as both tactics have their advantages! For example, carrying shield, longsword, mace and such all together can put quite a strain on your weigth limit, so its good to keep that in mind aswell