Yeah, take it easy for the first few balls - I recently bought an ICD Promaster cheap (was desperate) and out of the box I just let rip and it was an instant soup-cannon. Take it easy for 20 - 30 balls then work your way up.
Usual suggestions for first ups for an Ion are a new barrel and a new feedneck, but play with it first, see what you like, see if *you* feel that you're unhappy with a certain part. Don't just follow the stickies in the tech forums for Ion Ups, go with what you feel it needs. Also, take it slowly with ups - if you go out and blow a load of cash and completly overhaul it in a weekend, you have no more ups to look forward too