I added him to the party, but within five minutes took an intense disliking to him - annoying voice, annoying characterisation, and just generally got on my nerves. Fortunately, since I was still at the Five Flagons, I could drag the party upstairs, and swap Kido for Keto. What a difference ! She had me giggling out loud at some of her comments within minutes, and despite not really fitting in to the alignment of the party or the intended playing style, I'll keep her in the party as long as possible (don't yet know if she leaves if the party's reputation gets too low).
Anyway, if you're looking for a well-written and nicely-made mod NPC to include in a BG2 party, I recommend Keto. Kido ... well, not really my cup of tea.
Perhaps not-so-coincidentally, Ariena was done by the same author, and unfortunately falls into the same category - I can see what they're trying to get at with the characterisation, I just don't particularly want that character in my party (Ariena has lines like "Me Half-orc okay? I been pit fighter for many a moons! I not been edumicated... or something." and "Ariena no knew you is so weak. Me no want fight for a weakling." ... and so on). Unfortunately there's a lack of reasonable evil-aligned fighter mods NPCs around[2], so that'll mean grabbing Korgan, or maybe waiting until ToB and grabbing Sarevok.
[1] The unmodded "default" party (PC Sorcerer, Minsc, Jaheira, Keldorn, Imoen, Aerie), the "Mod NPC (good-aligned)" party (PC Geomantic Sorcerer, Amber, Angelo, Auren, Branwen, Yasraena), the "mostly Mod NPC (mostly evil-aligned)" party (PC Anti-paladin, Ariena, Miriam, Viconia, Ninde, Keto), and the LoTR themed party (Gandalf, Frodo, Legolas, Gimli, Arwen, Aragorn - all created in multiplayer mode, no NPCs).
[2] I do have another evil fighter NPC mod installed - Kindrek. However, then I read the Readme that comes with it, and the restrictions he puts on your party are a bit extreme (for a start, he can't use magic items, won't allow himself to be healed by magic, conflicts with mages, Aerie, Keldorn, and just seems to get in the way of the party more than actually being useful). Strangely, I don't want to play Kindrek Gate: Shadows of Kindrek, so I gave him a miss this time ... and probably will next time, and the time after too :-)