I aim for a top 10 place at mine, just as a bit of fun. It's absolutely about consistency. I'll always fall out of the running sooner or later through having to miss parkruns but it adds a bit of interest while I'm there or thereabouts. Don't forget to volunteer three times - 100 points for each, but no points for volunteering after the three .
I'm in Kings Heath Running Club, if you want something a bit less "full on" than the BRATs. Very beginner friendly, informal, and anyone's free to run with us, member or not. It's a good intoduction to club running. Facebook page gives a flavour of the group. https://www.facebook.com/groups/248229563140/
I'm in a similar position - raced last week, loosened the skin on the front of my heel, got a half marathon next week. I've taped it, and tried to keep as much weight off it as possible. Certainly no running. It feels much more comfortable now, To be honest I'm assuming I'm not going to be fit to run on the weekend, but that's based on the fact I've got other events coming up soon that I care about more. If it was an A race for me I'd put a ton of tape on it and pick up the pieces later.
I don't like the sound of your suspected underlying tissue damage. Just remember if it hurts after a 7k easy run it's going to be absolute murder on a 13 mile race. Personally if it's hurting at all on race day I'm not going to think about racing, because it's only going to get worse, probably a lot.