If you have a 5wt already then a 7 should be your next rod up and a 3wt your next rod down.
My 5wt is my all around rod and I use it on the Bow to nymph and chuck streamers. I also like using my 7wt in the winter when I know I'll be nymping or chucking 100% of the time. My 3wt is used on those Mt streams but It's seen the Bow a few times and is a blast.
Leap sizes
4 6 8
3 5 7