Use Haks.

[Finktank]

I played on a server for near five years that had over 3 gigabytes of haks at its height. It had just about every kind of hak you can imagine.
 
From my personal experience, the servers with haks seem to bring a different kind of NWN player to the server. I've played on two servers that haven't used a single hak, and one that has used haks up the wazoo. The servers without haks had a much, MUCH more in-depth atmosphere and environment with higher quality RP and DM quests. The one with haks just looked pretty, and people were more concnered with just looking pretty.
 
The other big issue with haks, even those like tilesets and new armor/head appearances is half of them are bugged to hell. Most custom tilesets don't have a minimap appearance to go with them, so you get a white box. Lots of them let you shoot through walls, or have invisible walls that don't let you walk in a certain direction, or another annoyances.
 
Just a newbie's two cents. ;)

[Dhund]

Yeah, as Finktank said, once you start adding more and more options soley to be pretty, you get people devoted soley to being pretty.
 
Also, the lack of haks does make it easier to convince someone to give the server a try on the fly, without having to download a few hours of haks.

[Listen in Silence]

I'm already devoted solely to looking pretty. Bring on the haks.