Phillip,, As an owner of same camera my self I aggree with your advice, especially buying a tripod over a lot of lenses. The tripod is worth a few f-stops.
Reference you image, I would have got in much closer to the flower heads, F5.6 on Aperture Priority, short focal length to give more bokeh to the background and fine detail of the flower.
They look a bit like some sort of Iris, but I am not a flower expert, but grow vegetables in my retirement as well as learning photography. I have had some succes with long exposer (30s) vehicle light trails with the camera, but you do need a tripod. A second is a long time on photography and 30 seconds seems like 100 years.
I borrow a lot of books on photography from the library for study of techniques, ideas and general enjoyment. Try John Freeman, Michael Busselle,Graeme Harris,Tom Ang, Digital night and low-light photography / Tim Gartside, Scott Kelby,Michael Freeman, just for starters. You cannot go wrong reading any of their books.
Practice & try different things, fast and slow shutter speeds on falling water, without moving the camera.