Now to me it looks okay (not great) in the front, the back is a bit awkward looking, however its hard to really tell because of the shadows. Some shots from the side would be nice to see if it is sitting even on her. It does look like its sitting a bit higher in the front would could indicate that its too narrow.
If you get some shots of your horses back shape we could try and recommend some saddles for you. Have you tried a wintec? They come in a wide tree and have super wide gullets available. They are also pretty cheap, usually run around 250-350 for the older models used.
RH Queen O Anywhere "Sydney"
2009 Sugarbush draft