Okay, basically you should set yourself BR goals. Read up on BRM carefully , work out your style and how much of a cushion you want to have at a certain level. How much are you willing to lose when moving up? These arent question someone can just answer for you, in short.. its up to you. If your just playing 2NL becasue you can crush it, and dont want to move up in case of losing that fine, but you must realise that youll gain money at a much slower rate at 2NL, whereas if you put some time in to learning and crushing 5NL the $$$ come much quicker.
Now i was in your situation about 3 weeks ago. Mr BR was brushing $200 and i was getting tired at 2NL. However i realised that if i moved up id only have 20 full buy ins. This is plenty for some people, but im a bit of BR nit, so i decided to stay at 2NL and grind out another $50, before hitting 5NL (25 BIs). I also set myself strict rules, if i dropped under a certain amount id drop down, grind back what i lost, and move back up again. Indeed I dropped down twice before settling in for the long run. Now my BRS up to over $600 (this includes 10NL adn some tourney wins) and im having a looka at 25NL maybe in a couple of week. Seriously you have to work out your own BRM, and stick by it. Spend a day doing research, looking at your game, then write a small doc. in work setting out a plan, goal, and fall backs. It will REALLY help your game.
If you want my opinion on 2NL adn 5NL they are basically the same, just with bigger stacks. Dont be afraid to make or call bets at 5NL just because they look bigger, thats only in relation to 2NL. There's just as many (if not more) fish at 5NL as 2NL, and its really crushable as long as you dont play scared.
Not sure how much of that made sense, ive been drinking . Ill look at this tommoz and clear up what i mean.