I probably have gotten the most use out of some 9' spinning rods I built on flyrod blanks. 6 weight is about the smallest and up to 9 or 10 weight for bigger lures. The key is to get a fast tip rather than a slow action. A lot better for snapping small jigs a long distance without dislocating your shoulder. A 10 or 12 inch rear grip on the rod is adequate for leverage casting and fighting fish on the long rod.
I also use these rods as "bubble-chuckers", for fishing water-filled bubbles far out on lakes when the fish are not near shore. In case you haven't tried it, that is a good way to present a big bushy streamer or bugger to smallies too...especially when they want a slow presentation. Just chuck it out, count it down or wait for it to settle on the bottom. Then use a variety of retrieves until you find what works.
Oh yeah, that works great for long distance presentations of small weightless plastics and Gulp minnows too. Be sure to rig "Carolina rig" style with the bubble...with the bubble sliding freely on the line ahead of a swivel and leader. If you keep a tight line you will easily feel even a light tick.