Obviously a late reply, but I'll still do it for the benefit of anyone else that reads this thread... I think that the answer depends on what you're intending to do with your rogue. If you want a rogue that maximizes his skills and sneak attacking potential, stay with a pure rogue. However, if you don't care much about sneak attacking and want a rogue that is a little better in standard combat, then perhaps take some fighter levels. Or if you'd like your rogue to try to maintain his skills, but still be better in standard combat, then perhaps ranger levels are better, since you'll be able to put plenty of points into the stealthy skills and search, while still getting the HP and BAB of a warrior class. Taking barbarian levels might be a bit similar to taking fighter levels. You won't be able to take all that many useful (rogue) skills when taking a barb level, but you'll get the barb HP and BAB. After taking the first barb level, where you'll get your first daily usage of Rage, you won't get another one until the 5th barb level. So, I'm not sure if there's all that much value in taking any more than one level of barb. Personally, I'm not sure that barbarian is such a useful multiclass mix-in for a MC rogue, but tastes vary. On the flip side, an interesting multiclass combo that I've enjoyed is a mostly pure fighter that takes a couple levels of rogue. The purpose here is to have a mostly pure fighter with all the normal benefits of a fighter, but with some stealth and the evasion ability. Of course, to get the benefits of stealth and evasion, such a build should have at least a DEX of 14, and probably wear chain armor (and it might be a good idea to take the lightning reflexes feat as well to improve the reflex save roll). And it'll need to have a decent INT to get some skill points. With such a build, I'd suggest starting as a rogue for the initial burst of SP's at creation, then go pure fighter for a few levels before taking the second level. Another benefit of this build is that it can be the party's diplomat, if you want someone different doing the talking other than the usual candidates. Of course, you would need to keep the CHA at a decent level and you might want to put some SP into talking skills when taking rogue levels. While it's not a powergaming build by any stretch of the imagination, it can be a very fun build to play in a more role-playing style of party. And 2-3 levels of rogue really won't kill a nearly pure fighter's usefulness in combat.
thanks for the reply, after original post I ended up going with a weird rogue/fighter/barbarian all-in-one combo. Barbarian speed has its uses but it bugs me when the barbarian bumps into the slower characters, or speeds too far ahead of them, plus the reasons you stated, so Illl give the barb class a miss next time. I like the sound of ranger being able to buy sneak/hide points, so may consider rogue/ranger next time, otherwise I may go just for rogue/fighter combo for the feats.
I'm not sure that there's a lot of value to be gained from adding "some" levels of druid to a barbarian, just to get some shapeshifting. I've never used druids all that much, and even when I did, I hardly ever used their shape shifting at all. Also, I'm uncertain if barb rage and shapeshifting will work together. They might, but they might not. And I really don't know one way or the other. I could possibly see adding some bard levels to a front line fighter, if he had a decent CHA for the talking skills, and a decent enough INT (to get a decent # of SP's to buy those talking skills). In fact, it might be even better to take rogue levels than bard levels, if it's strictly for talking skills, since rogues have access to all 3 talking skills and get the most SP/level. However, I could argue in favor of bard levels (instead of rogue levels) for a couple of reasons. A. Even with a single level, the bard/ftr could use the level 1 bard song that gives some combat bonuses to your party ... though you'd absolutely want to invest in the Lingering Song feat. Bard songs without the Lingering Song feat is a bit of a pain, if you intend to do anything other than stand around singing... which would not be the case for a front line tank. B. There are some VERY nice bards-only items that a bard/ftr could use. (My personal favorite is the Horn of Valhalla which summons 2-4 berzerkers to aid your party once a day.) It's worth noting that a small number of rogue or bard levels on a front line Fighter character really won't harm his ability to be an effective tank. I've played a Ftr X/Rogue 2 build before for much the same reason ... to be the party spokesman. I treated the character as sort of a "warrior poet". She was hardly an optimal powergaming build, as her stats were STR 16, DEX 14, CON 16, INT 12, WIS 8, CHA 10 (human female). But she was managed just fine as the party's #2 tank and party spokesperson. As for a fighter taking a single level of ranger, I'm not sure what the point would be. Oh, a traditional reason for taking a level of ranger is to get the "free" dual-wielding that comes from the first level of ranger. But remember that it only works when the character is wearing Light armor, or no armor at all. If the fighter is a plate or chain wearing type, a single level of ranger would be largely useless, if your intent was to get free dual-wielding.
