You'll need to do the appropriate engine work to take advantage of the carby... I recommend you read more of the forum before running out to buy more parts. If you can, swap the 28mm for a 26
Look into free performance mods like deburring the inside of your intake manifold and matching the intake to the carby adapter... The tech section will be your friend. You're going to have to do some reasonable engine work to take advantage of the bigger carby (otherwise you'll find it bloody hard to tune and it will likely never be right), start by looking at different heads + exhausts.
A rear shock wouldn't go astray (something from DNM or Factace), and change the oil in the forks for something a bit lighter to match. You can upgrade your forks too (if you're willing to commit the $400+), have a look around on here to see what people recommend.
You can look into different bolt on parts (ie, kick start lever, gear lever, brake/clutch levers etc) too... Do the basic stuff first, do all your research and get out and ride it before you decide what you'll need.
Good luck!
PS, make sure you do all the initial setup/greasing and run it in right too.