We are all volunteers, and everyone contributes in whatever way they want to. No-one tells anyone else what to do - people ask each other for help, and the person who is asked is expected to say yes or no according to what they would like to do - it is totally OK to say no, just because you don't want to! So we avoid pressuring each other into doing things, and we try to avoid power relationships, i.e. we are non-hierarchical, and everyone is expected to take responsibility for only taking on those things they want to do and have the capacity (time, energy, etc) to do.
Stepping forward, stepping back It is ok to step back. Unless we are sustainable in ourselves, we won't be sustainable in what we do. If that means we have to step back from a project, so be it. If no-one else comes forward to lead the project, then we let that project become dormant (or even dead).
If someone has an idea, they put it to the relevant group (which they would usually already be a member of) and if there are enough people with enough enthusiasm they will make something happen. However, no-one makes long term commitments from the start, which you would require. Also in Transition we start small projects and let them develop organically. We do not start with a grand plan. Finally, no plans are likely to get support unless the instigator is also involved from the start and the fact that you are based in Shropshire makes that very difficult.
I suggest you select a small part of your plan and see if you can get it going near you. Then assuming that is successful you could showcase it through the Transition Network for other groups to try out too. If your food gardens project is going well, perhaps you could start from there. I see it has been going only a little over a year and I don't see any endorsements on your courses - have you considered asking your trainees or volunteers for feedback that you could use to promote your courses?
(obvious examples include that we are not party political, that we propose alternatives rather than campaigning against things, and that we encourage people to take a lead rather than expecting others to ideas for others to do)
We keep to things which are legal! (i.e. no guerrilla gardening, and we try not to use words like "seed bombs")