Craigw is right about the engine shed... I'm now considering not including one at all. I don't really want to change the layout significantly as I've already settled on most of the layout being the way I want it (for example, having the platform facing the front of the layout, having the goods yard at the front etc.) which means there really isn't anywhere else to fit it in. In reality, as I've admitted before, an engine shed would be something of an extravegance for such a small terminus anyway, even though I like the idea of modelling one.
So here's the track plan without the engine shed. I've also rotated the whole track plan slightly - bringing the left-hand end closer to the front edge of the layout. I can imagine the view across the railway tracks with meadows sloping gently up towards the backscene (where a hedgerow could disguise the join), similar to Stephen William's Faringdon.
The drawback of removing the engine shed is that it means less operating potential. It's a difficult line to tread between getting the appearance right (spacious and uncluttered) and having enough operating potential to sustain interest. One idea is to try and fit another siding into the goods yard...
...which works in theory (there's sufficient room between the tracks for loading and unloading etc.) but in practice might look too cluttered. For example, the picture of Farindon's goods yard at the bottom of p.78/79 of Great Western Branch Line Modelling Part 3 is absolutely the sort of spacious feel I want to acheive, and this might be lost with too many sidings too close together. The only way to really decide this is to print out the two track plans full size.
If only I'd made the baseboards a just that bit wider - another 6 ins would make all the difference but I'm stuck with 2 ft now - there's no way I'm starting again!!! (I can't move everything back any further as I need to allow enough room for the station building and I'm not a fan of low-relief buildings.)