This is the sort of tune, along with others like 'Wildwood Flower', that you can sit and noodle with for hours. It's great fun and becomes very creative once you get into it. You can use extended and altered chords, chord substitutions, all sorts.

In the example below, there's a G7+ sound in bar 4. The C7 changes to a C9, and the F is coupled with it's relative minor Dm7.

Again, it should just roll along fairly effortlessly and it's a great way of discovering new licks, tricks and harmonies. Good luck with it!