While I agree with minnflyers advice

I think it is going to be difficult to predict what your second plane should be before you've finished building much less flying the first!!! Who knows your "second" plane might be another trainer

I would hold off building another plane unitll you have some type of clue of how quickly you will aquire your flying skills.. Although the mid-stars and easy sports are good choice for a second plane (had an easy sport) .