Chris,
good luck with the new house.
We've recently (well still not finished) been renovating and converting an old place.
The daft thing is all the goals set, which are generally just an arbitrary figure.
All this low emissions etc takes little account of how the buildings will be used.
And if you struggle to meet the figures because, for example, you have a large glass area to make use of passive solar, you can offset this by doubling the loft insulation, regardless of whether its actually being effective or not.
We chose not to go with solar panels as the payback period is too long, and we're surounded by mature trees so they would go green (with algea) in no time at all. We do collect rainwater though. Funny thing is, the calculations show that to run the pump to pump this up to the header tank for use by the toilets actually costs more than to use mains water would...
Like you say, if it makes you feel better for what you do, thats great.
We burn a lot of wood too, all of which comes from the trees in our garden. Some say this is not good, but recently its become acceptible as its considered carbon neutral now, and it does after all mean we use less gas for heating.
I do like the idea of do what you can locally, but thats more becuase I get fed up hearing about how we should be helping the other places in the world sort their problems out. We have enough problems of our own to worry about.