Ill tell you what ive learned from years in actuall card rooms, not online. I dont know much about staking online.
You only accept a stake if loosing is on the staker. So, if you are given $500 to play with, if you win, you each take 50%, if you loose, you dont owe. Otherwise, its not a stake, its a LOAN. and a poker loan can be as bad as borrowing from the mafia. Staking is basicaly for full time players, that make their living playing, and are very confident in their ability to win.
You say your not too profitable at med/high levels, so at this point, a stake is not really productive. And anyway, usually someone will only be staked if they have lost their bankroll, and need a wealthy beneficiary that knows they are talented to get them started again.
Staking is high risk for the investor, so I dont see why someone would offer to stake someone that didnt have visible results to prove the odds
of gaining profit vastly outweighed the potential loss.
Put it this way, would you take your hard earned money and put it behind someone you didnt know, or werent sure if they were very good players? no, youd want to put it behind someone like phil ivey, and thats because you KNOW that his chances of turning it around into big profit is good.