You cant worry too much about what other stacks at other tables are doing, just focus on your table. I play alot of MTT's and tend to cash more often than not, except for the last few I have played but thats another story. I had donkitis. Anyway, you have to pace yourself and stay ahead of the blinds so they arent killing your stack. I say patience and dont be afraid to push when people have folded around and only the blinds and button are left to act. The bubble is by far the time you will see more all in action since the short stacks are trying to survive into the money. Along with weaving through the early all in fest at the begining. As far as the buy in level, I like the $10 or more, tend to be better players. This is JMO and a bit of the strategy that I use. Good Luck