Seeing how your dollhouse is displayed in a solarium with a seemingly beautiful garden in the back, it makes sense you are from the UK. With all the 1000's of posts on this site it is easy to get lost in the multitude of opinions and experiences. For instance, are you saying you have used hot glue on the whole dollhouse and never any wood glue? Doing construction myself i rely a lot on epoxy, and have read many articles on how not to prime the exterior before you wood glue and clamp the details on, such as siding and shingles. As long as it holds up to being well loved by 5 small children I am up for attempting any of your suggestions!
I would have never guessed you used any sort of stone effect on the shingles, maybe that is why they seem satin or dull finished from the pictures. Your choice of color offset is remarkably accurate, i live in Ohio so slate shingles are common on turn of the century homes and what you have done on your Garfield is wonderful. I'll still make sure to practice!!! From some other posts i've heard that a satin finished exterior paint is best for being wiped down and keeping the 'grimy fingers' look at bay from handling.
I see what you meant about the roof peak being simple shingles, in fact i like it better than the gingerbread it makes it feel more real. The 'cap pieces' i was referring to are what hide the roof seams over the turret. another ingenious invention of yours? I can find balsa wood at a local hobby store to experiment with on my own. Its difficult not having a woodshop at the moment!
If you have a link to this Russian Lodge of yours i would love to see more of your work! I've found building small homes, etc is rather therapeutic while i save up for the real life projects i'm striving to afford.