I play basically these exact same tourneys every weekend.
Here is my basic strategy:
early game (deepstacked) play basically tight. You can definitely set mine in any position if you stick to a budget, and you can play speculative hands in late position (like 97s). avoid trap hands like KJ
middle tournament: this is where most of the skill lies. above all else, consider your stack size relative to the stack sizes of your opponents. Maintain your fold equity no matter what! If making a certain move, bet, call etc. will kill your fold equity in the future, then either pass on that move, or just go all in. You don't want to be left with a stack that doesn't threaten anybody. If the blinds are going up in a couple of minutes and you know that once that happens your stack won't be able to get anyone to fold then JUST PICK A SPOT to get in in asap.
Do NOT blind down in the middle. THE MIDDLE IS WHERE YOU TAKE SOME RISKS TO BUILD A STACK. for a few reasons: #1 the blinds are finally worth stealing. #2 re-stealing is REALLY valuable to your stack #3 weak players for some reason go tighter at this stage once the blinds are big relative to their stacks; it's opposite of what they should do but they are WEAK and they usually just like to splash around for cheap in pots. They are much less likely to call your bets now that the blinds are big. #4 the middle is what sets you up for the final table. I can't tell you how many times I've seen players build a stack early only to donk it off before the bubble, or to blind it down by the bubble. But when a player builds a stack in the middle, they usually go deep. Don't be an early bird, be a middle man.
my tips for playing the middle effectively: never fold a big draw, play them aggressively. be happy to push it in with 12+ outs on the flop, when you add the fold equity I think monster draws is HOW big stacks are made; this is that part about taking risks to build a stack. re-steal liberally if your image supports it. pressure the nits. be acutely aware of bet sizing and stack sizes. Probably can't fold any monsters, at least never preflop; can't fold QQ, JJ, AK preflop in most cases. You will probably have to win a flip or two in the middle. That's just the way it is.
EXPLOIT THE BUBBLE: Find out who at your table is just trying to hold on for a cash, and raise them relentlessly...but if they fight back at all, back down. they must have a real hand if they're willing to commit chips.
AFTER THE BUBBLE BURSTS: sit back and let the all-in fest happen. stay out of the line of fire unless you're packing heat.