General Improvement

Actually, the most important thing is to have someone stronger than you to go over the game with you afterwards. Which does not necessarily require that person to be whom you played. That said, if you play someone a lot weaker, the game might be too low quality to go over.
If you have no one to go over games with, post a loss in the analysis forum here. Without help, it is difficult to get much from a loss. That said, you are encouraged to attempt your own analysis before asking for help in the forum.
As far as whether to play up or down in a tournament, Bobby is correct that you need to consider psychological factors. We are all human, and few if any of us like to get a terrible beat down.


mmm
I see that about EVERY rating number. its a given, I think, that you'd be Higher if you quit "hanging stuff"
but just like saying "I need to quit eating less fattening food" is not helpful for people that need to lose weight- I don't think "Quit hanging stuff" helps people break the plateau
'just sayin