G'day Denny,
My shortlist would be American Ideal, Artistic Fella, Art Major & Sutter Hanover.
The reason I chose those 4 is simply that it has been my experience to date that they will each leave quite substantial foals...of a good size with good length of barrel and leg & overall good bone/muscle to them & seeing as your mare's on the smaller & fine boned side... that sort of sire should really help her do her best.
An example of going back the other direction is a mare we have, a thumping big Shark Gesture filly who's a bit on the raw boned side like her old man and much of the stock of her grand father in general, also has a touch of the Roman Nose for which her grandsire was so noted...and she has been bred to Shadow Play because of his overall refinement. That's one mating that I am really keen to see the result of.
I also like Sportswriter a lot but I haven't seen any of his foals so how he leaves them (size wise etc) I cannot say, although I can't recall many sons of Artsplace that left small, fine built offspring. I think Artiscape was the only one.
I don't get hung up on bloodlines all that much, on this cross or that cross etc etc etc.
I might get howled down by some but IMO it's far better to focus squarely on Form & Function & basically don't breed mice to mice nor elephants to elephants.
You don't always get an average of the sire and the dam of course, sometimes things come from out of the blue, but generally what I try to do is mentally overlay the size and build of the sire over that of the dam if that makes sense, kind of like lining up a couple of old photo negatives on a light desk, one atop the other.