You could do a SE imo. After they add H5 a SE actually becomes a playable class.
ye but he is gonna have to solo/random party for the next 3 month, which might get him bored, picking a sws or bd will also be a good choice since h5 is coming and they become more awesome to play and he will most likely have someone to play with. Well actually alot of classes become awesome to play so it really doesnt matter what you pick, pick w/e you feel most comfortable playing, smth that wont get u bored easily. If you want to check what new skills ur class gets visit http://www.lineage2.com/news/highfive_01.html
, for full list of skills visit http://lineage2.rochand.com
there is the list of all the skills updated to h5.