In a campaign I run regularly, I've got a BBEG who is a sneaky sort, I've got him imagined as a gestalt Swordsage/Ninja 10, seeing some interesting combinations of abilities with the two classes. However, I'm having a difficult time going through the large numbers of abilities, feats, magic gear available and selecting a batch of them.

For a little background, the last time they went up against this fellow, he was a straight Ninja, and it seemed that the limited number of actions, combined with low damage and weak survivability, made him pretty easy to take down, and resulted in a fairly anti-climactic battle, in which he was beaten down almost single-handedly by the party's low int barbarian, forcing him to flee after 2 rounds, despite waves of minions they had to fight through before hand without a rest. (They aren't exactly major powergamers, either, most of them are playing pretty tame stuff, like poorly put together bards and straight class fighters, with one player who is a notable exception, playing a batman type wizard)

I'm looking for round two to present more of a challenge, however, at the same time, I'm not looking to floor the party, so I'm not really after the most optimized builds around. It's safe to assume this character has the resources on hand to manipulate and seperate members of the party and attack at times and locations of his own choosing, and the members of the party will likely be around levels 7-8 when this occurs.

I'm hoping for something looking at Setting Sun, Shadow Hand, and Desert Winds, as they seem to fit the character better than the other schools.

I'm going to avoid giving more specific details about the party composition, as they will likely recognize their own characters if I do, as some of them frequent these forums, and will likely read through this regardless of whether I ask them not to.

Whatever help you can offer me would be greatly appreciated, as other things have left me with much less time to prepare for my games, and it's having a noticeable impact on the game.