03 Polaris

I'm green as a gourd to the pwc world but I think I got a decent start. I just bought an 03 MSX 140, 30 hours, cover, vests, skis, tubes....and a custom built and painted trailor for 3K!! I must say so far it's been a blast. I've hit 64 with a half full fuel tank and the thing seems to have very quick take off..
I really haven't figured out what to do with it yet. I may try to teach my 10 year old to wake board...
Any suggestions on performance upgrades or any info in general I'm all ears.