Another issue with the A319 is the stands. There are only 10 of them (I think) and they are tiny self-manouver ones.
Not sure how agile the A319 is on the ground but even the D8 400 can't get itself on stand there without causing a lot of commotion (one of the many reasons flybe binned that idea).
Seems to me building a parallel taxyway would be easy compared to trying to expand the ramp area!