If you're #300, I would recommend the spring upgrade for the rear shock, and sending the shock(s) to Pioneer for a re-valve. I'm #240 with gear, and I ride aggressively and bottom the rear suspension at least 100 times on each ride!
There are enough ski debates on this site to confuse you for a year, but at least ditch the stock carbodes in favor of Bergstrom's, or Dooley's or something else. The 4" factory carbides didn't make it 100 miles on my sled, and with 8" Dooleys it handles much better, but mileage has suffered.
Take some time and browse through the site. there are hundreds of idea here on how to improve handling. It all depends on how far into it you want to go.