I came second in a tourney last night (brag) and my tactic once i reached the final four was to rasie raise raise. I'd accumulated a big stack and I just ran the table. Enter in to pots with position, always raise when you enter the pot, don't play trash but solid cards.
9 handed you want the same principles but in a more controlled way. Try changing gears. If you are comfortable then sit tight. Then start opening up notice if your blinds fold. which players fold to re-raises when they open light and such. Then sit tight again. you have a lot of info.
People will start thinking you keep going on good runs or are bluffing, figure out which. When they play back at you and you have a big hand you can snap them off, but if you enter with a marginal hand and get action just lay it down.
You can also play alot of small PP and suited connectors for flop value a syou can afford it if you flop a big hand you can break poeple.
This is big stack poker, controlled aggression with speculation. Don't try and make everyone fold post flop with stupid re-raises target specific people.
Oh and its very fun to be in this situation