Doing everything JAA in Europe is going to be very expensive.
Flying in the US is roughly half the cost if not less.
Doing an FAA commercial IR will be a great stepping stone for returning to Europe to do the finish up training. At least you'll have the experience already.
A lot of your time building can be done in the US, there is no requirement as to where the hours have to be flown.
While you're at it check out
www.eaa-fly.com
