Just as a note worth considering.... The wall girt is now joined where the tie meets and this may be a week point in the post, and causes pegging problems. Being a principle purling roof your rafter thrust is reduced so it may not be an issue. Lodging the joist on top of the ties means you figure the full size of the timber but when you cut joist pocket out then you need to figure the smaller size remaining after the joist pocket is cut, requiring a larger beam, which I thought your were trying to avoid.
The other issue I see is in relation to Ken's reply dealing with "poor design or ravages of time" thing when setting joist into pocket as described. Better than 3/4" pockets. There are other solutions which come very close to your visual requirements and deal well with the problems as I see them.
