Flouro is great for cranks because it sinks at a faster rate than other types of line, and can help your bait get deeper. If it were me, I would just use flouro and no braid. I'm sure using it the way you mention would work fine.....i would suggest an 18-24 inch (or slightly longer) leader if you do. Braid is very visible to fish and flouro has nearly the same light refraction as water....making it next to invisible to fish.