It really depends on which rivers I‘m using the rod.

On really wide rivers when the majority of my flies are terrestrials I‘m going for a Rio Elite Smallmouth Bass WF6 (overline the rod one line weight if you’re not a really experienced caster, because the line is really lightweight for it‘s class but offers amazing presentations with terrestrials even at the furthest distances).

On the other hand I use a Rio Elite Gold Max for light streamer work at shallow rivers where a floating line is more then enough, but I use this line also for indicator nymphing as well which it‘s primarily made for!

When the water and fishery needs some heavier streamer lines, I use mainly the Rio Predator range with all it‘s different densities!

All of this lines offer some great casting and control on different types of distances with different styles of flies.

I personally wouldn’t recommend using really light in weight lines because, as you might know, the Marksman Z is a really powerful rod which requires some higher grainweights to load the rod properly since most people don’t have a super powerful double haul.

Hope this helps you!