Should I leave when I have some some amount of money (like 200bb) or the more money I have at the table, the better?
leave when you
have no edge
tilting
low VPIP table/plrs per flop
lots of SSrs
full of nits
etc etc
anyways should also be maximing table scanning
If you think you have an edge at your table then yes I would say the more money the better.
However, if you are uncomfortable playing deep I think its okay to leave, especially if its not a particularly good table. The dynamics of the game change quite a bit when playing with larger stacks so if you lack experience in this area you might be at a disadvantage in such situations.
Keep in mind that if only you are deep on a table then technically your effective stack size is only as big as the second biggest players.
A lot of players tilt when there is a large disparity in stacks. If you have $600 at a NL $100 table, some players will go crazy. Some will call you down with weak hands trying to prove you are a bluffer. Some will tighten up a lot against you even though your extra chips can't be used against them.
On the other hand, be careful that you don't tilt when you have a big stack. Some players feel dropping from 4 buy-ins to 3 is not as painful as getting stacked from 1 buy-in, or they try to ride a rush and play unprofitable hands because they have been lucky so far. This leads players to waste a big stack.
Of course, you should also be aware of how the game changes with deeper stacks. Implied odds and position are more important when the stacks are deeper. If another deep stack is going to have position on you in most hands, this can outweigh a skill advantage, and it can mean you should leave the table.