Halifax are certainly an interesting case. As a club, they are well within the heartlands but have enough of their own 'patch' not to be overlapping with lots of other clubs, e.g. they are the only club within their local authority area. While not a city, it is similar population-wise to Wakefield and, as states, has a relatively healthy community game (not just Siddal). The stadium is fine and handily located for the town centre.
Having lived nearby for a couple of years, I think the club try hard to get kids into the ground from local schools/clubs but they face the same challenges as anywhere else in that most kids walk around in Man City and Liverpool tops.
I thought they were starting to build a decent team and put up a decent showing v Catalans in the cup, but their recent form has been alarming.