Such a brilliant design, but the mods really make it interesting.
I would reccomend Native expansion if you're starting out, it's basically the same as vanilla with some very nice new features.
Prophecy of Pendor is a good mod but it is devilishly hard, suddenly your early game weapons do nothing to anyone and they just stab you in the face and you die again and again and again, good fun though.
On the very first quest in PoP (saving the brother) I had to shoot the bandit hideout chief like 4 times in the face with a crossbow before he went down, he cut down like 16 of my boys, it was brilliant.