Having your Mom as a quilter will be a huge help in configuring how to make that top. My wife has been quilting for 34 years and has a long arm in it's own room in our lower level too.
Where did you find that tool box with Marty's name already on it, that is a "gotta have" item...
My son was given one of those train sets when he was young, but didn't play with it enough to expand, thank goodness. The cars may have wooden then too, If I recall ???