Strategy for NL Tourny with Rebuys and Add On

[Zybomb]

Next week there is a big organized game in my area with top place paying out over 20,000. Its a 50/100 blinds NL Hold Em with 2500 chips to start (im more used to 50 BBs as opposed to the 25 there are here). The first round is 30 minutes and every round there after is 15. Its a 55 dollar buy in, with rebuys allowed for the first four rounds, and 2 add ons (25 for another 2500) allowed before the break. Most of my experience has come in cash games and in tournies without rebuys, and my experience in rebuy tournies is fairly limited. I was wondering if anyone had advice on how to change strategy for this type of a tournament.
In the past Ive gotten annoyed as hell playing in these type of tournies, when someone comes in with 8x the buy in and has intension on using every bit of it, since he can get outplayed so many times and then catch a lucky break and still be a major player in the tourney. Its also frustrating knowing that in roughly one out of every 3 or 4 hands there will be a preflop all in, which kind of limits you to mucking unless your content on risking all your chips with the hand you have. My usual play is tight aggressive, with flashes of loose aggressive when i think the time (or chip position) calls for it. I limp pretty infrequently and come in for standard raises (usually 3x) in the majority of pots I enter regardless of my hand. It seems many players sit around waiting for a big hand and then push all in hoping to either steal blinds and limps or double up, and can always rebuy if necessary. It also makes players more difficult to bluff, as they will make loose calls knowing they can re enter.

Any advice as how to alter your play for these types of tournaments would be appreciated, and also your opinions on a range of chips youd have after the first 4 rounds to make the add ons worth it (too little, the add ons wont matter much, too much they arent necessary) Im sure if I can have a good position after the first 2 rounds, the next 2 wont be as bad, because the blinds will be up to 200/400 and 400/800, so the 2500 re-entrance wont be a factor during those rounds.... Sorry about the long post and let me know what you guys think