You might want to invest in a good mask first if you don't already have one. Something Dual pane. If you have a melon head maybe a Proto Axis, I3's (if you can find a pair) or Sly Profits. Maybe the flex 8's. Just something with Dual-pane for fog resistance and good padding for your face. You might have a game where you wear a mask for about an hr and bad padding and fogging lenses are terrible. You're no good blind and cranky.
The only advantage i see of owning a Tippman would be the flatline. Really the only major upgrade i can see getting for a long-baller or for the gun in general. The rest really is just personal preference/ flashy accessories.
To see if you have a big head, go to a local store and try on a hate that says, "One Size Fits Most" If it doesn't fit, then you have a melon head.