[Ubik]

Rogues are my favorite class as well and my current lvl 1 ranger/lvl 10 rogue is doing wonders in the late chapter 2. I've started off with an Elf, because the first time I went through the game (again with a ranger1/rogue xx, only human) I hit the ceiling way before end game, so I thought I could bear with the xp penalty - the game is quite easy anyway, so a slower lvl progress has proved intriguing.

The added Dexterity (With the addition of a couple nifty items I got it up to 25) works wonders in every aspect of the game (he is proficient in shortswords - dual weilding Feyduster and a +2 ss - and longbow).

I took only 12 strength initially and I haven't put a single point in it, pumping up my Dex. all the way.
A Hill Giant belt gives me more carrying capability and a henchmans does the tanking, while my finesse rogue strikes lethal blows from the flank or rear.

If you really want to take Fighter levels (I wouldn't do it, but it might prove interesting) I'd suggest four of them, and you'd still have to take that one Ranger lvl, for dual weilding (you'd lose two feats to get there, otherwise) and the racial enemy feat (undead and human are definitely the best - actually the only viable - choices there).

In this case you'll suffer a hefty exp. penalty - dunno if you can live with it.

Cleaver might be an extremely interesting feat to get for your rogue xx/fighter4/ranger1 character.