At this level....become a bonus whore
Forget rakeback at pokerroom/ poker network.
Just don't sign up for the room that offers rakeback yet. Whore all the others. They are taking turns offering 7X deposits, 10X reloads, etc. Worst case is the 15 or so skins that offer 12X. At 7X, you can make about $30/hr 4-tabling 2/4. Sweet stuff. Even the crappy Hollywood $10,000 bonus pays 18X if you do it all. That's an extra $12 or so per hour.
PokerNetwork's 8 gajillion skins and other rooms I cannot believe I gave this advice out---so much for good games on the PokerNetwork.
BTW-Most rakeback at the poker network are contributed rakeback, which is lower than regular rakeback for TAGs.