RP server or not, combat is a huge part of it or there would'nt have a level 20 cap or so many dungeons. Stat nerfs are only a secondary concern when a character is RP first or only (even then they matter to an extent as they represent something). Even then, if Kagonesti are like wild elves, I am going to simply say that it seems illogical to only give a +2 dex and two negative penalties. Wild Elves are the phyiscally challenged as a result of how they live and behave and require stamina, agility and a degree of strength in order to survive as a people and individuals. More so than the other subraces on average. It seems only +2 dex and then the -2 int/cha is misrepresentative in my opinion regardless of the existance of other nerfed subraces. Even the -2 CHA is questionable. Elves are considered beautiful, period. But only some subraces (to my knowledge) get a CHA bonus such as Drow. Dragonlance lexicon says that Kagonesti are beautiful to non-elves but viewed as exotic beasts by their cousins. If the racial adjustments are altered from the original, then theres no reason to stop there? Remove the cha penalty. A Kagonesti's beauty, leadership potential and charisma is not automatically hampered by their birth. Then again I never liked the way CHA is represented ingame but that aside. They're not uglier than other elves, they're looked down on. They are no less charismatic, charismatic individuals are that which they follow and there are more forms of it than simply being pretty to look at. Finally social graces are entirely situational, depending on the society.
In summary: My opinion is add a str/con bonus to the dex or remove the cha and any inbalance is corrected. Other subraces which are unbalanced does not seem like a valid counter argument as there needs to be some reason that they're inherently weaker than other types of that race. If you use it as an argument, it seems to me that you are saying Wild Elves are inferior (represented by net -2 stats to every other elf and standard nwn race), and I don't think thats true.