Line for Sage Z-Axis 5110

I just picked up one of these switch rods and I'm looking for a line for two handed casting. I'm currently using a 6wt air flo 40+ with 10' poly leaders and that's not a bad set up but I want one of the floating shooting head systems like AFS, Vision, or elixir. Without going the custom cut route, I guess my choices are AFS 4/5 @300gr, Elixir 5/6 @295, or Elixir 4/5 @245gr. Given that I'll be using air flo floating and sinking 10' poly leaders to fish soft hackles and small streamers am I better off going with the lighter Elixir 4/5 to make sure I don't bog down this small rod? Thanks for any advice and I'm open to any other options.