Heh... I have trouble finding the time to play both, though it is an absolute blast playing totally different characters. You get to know, as a player, much more about all the characters you RP with on a regular basis. Pyyran knows Cole Norseman as just a mindless, drunken merc, whose sense of humor lacks a certain... Wit. However, Cynn Reyer, Cole's apprentice, gets to see a whole other side of him, and, through her, so do I. Since I started playing Cynn, I've gained a great deal more respect for Miltonyorkcastle as a player, because I see now how complex his characters really are, and how well he plays them.
Also, I tend to get very into character, and Pyyran and Cynn's tempers are quite different... I was much, much more irritable with certain characters, and, unfortunately, thier players by extension, before I started playing Cynn a bit more in-depth. A lower CHA with a higher WIS... That makes a much more agreeable person. *He chuckles.*
The totally different playstyles also make the game a lot more interesting; as Pyyran, well... He's your usual swashbucklery rogue. He'll stand behind the fighters and Sneak Attack anything in range, usually dealing damage like someone three or four levels higher. He can also Sneak near-on anywhere he pleases, and he's HUGE into crafting, particularly Alchemy. As such, the way I play him has evolved around all of that; the way I play Cynn, out of necessity, is very different. Cynn's AC is ridiculously low for a fighter of her level - only 20 at level 6. With a Helm of Armor I, that goes up to 23, and then Expertise boosts it to 28. Still rather low. Her focus is on the Greatsword, which will dish out a huge amount of damage, but precludes the use of a shield. Also, she can't Tumble worth a flip, so AoOs are a common thing for her. Ergo, the way she fights is very different. She's no crafter of any sort, so I don't spend my time collecting Catnip or Cranberries while I'm playing her, and because of that, I get a little bit more chance to RP and party up. As a primarily Melee fighter, she also fights very differently from Pyyran, who uses his bow almost exclusively in Party.
All in all, it's a totally different experience. When I get a bit more time on my hands, and get Pyyran to Duelist, and Cynn to Weapon Master, I'm likely to start in on a spellcaster of some sort. Very likely a Druid, because I've never played one before, in PnP or NWN. When it all boils down to it, the only purpose for having multiple characters is to have more fun, and usually, you won't need seven characters all active to do that. We're here for the RP, and the fun of the game. So go for it.
You've got my input, so there you go.
Cheers,
~ Stephen (Exp 4)
Pyyran Rahth (Rog 9)
Cynn Reyer (Ftr 6)