Nick should've stayed at the Colonia afterall..
Instead of running, they should've use Ricks strategy back at the prison when the Governor rolled around at the end of season 3.... let them feel like they won going in, then when the gangs are surrounded by walkers, another group should fire into the gang and cause disarray.
Finish them off and continue staying there. But the question remains of how long can they supply themselves once the food / water dries up...