Tango,
You dont have to do the FAA PPL, you can go for the FAA CPL as long you meet the other requirements. I did the same thing, got an FAA PPL on the back of my JAA, did the IR, then the CPL in the ME. Added the CPL Single engine and then got the ME IR added.
I did however find myself in the weird position of not being able to fly SE once I got the CPL ME as according to the FAA the reciprical agreement does not apply once you get a professional licence. Hence once I got the CPL ME my PPL SE privledges were no longer valid and whilst I could fly around in multis I had to wait until I got my CPL SE until I could fly them again.
My training provider got caught out as he had not had a student request to do his initial CPL in a multi before so he learnt from the experience as well - so watch out if you go this route!
Julian