Grab Jonas Valanciunas ASAP. Raptors have no reason not to start him the rest of the year. If you have to drop someone for him, I would drop Okafor.
Try to trade Evans, Bogut, AK47, Nene, Collison and Mullens for players that you can actually count on. Bogut and Nene are especially big liabilities.
I hate to say it, but your team is a bit of a mess, a lot of big name players that don't produce as well as some of the lesser knowns out there. If this is a keeper league, it might be time to start planning for next season. Your best players are Kobe, Nash, Griffin and Wall, not a bad core, but certainly not the best or deepest one. Time to start rebuilding.