fluoro leader? or line the whole thing w/ fluoro

Depends on application and water clarity.

I think it’s a less common to go full fluoro, except some crankbaits and jerkbaits where you want a little stretch and line that sinks. In this case I like 12# straight fluoro.

I like 30# braid and a 20# leader for jigs, Texas rigs, chatterbaits and other single hook lures. I fish in relatively clear (3-4’ visibility) with a lot of thick grass. I think it doesn’t matter at all if water is dirty.

Base your leader weight on how much cover is around (8# for open water, on up from there depending on cover). To me it’s worth getting a nice brand since you’ll only use 4-6’ of leader at a time typically, and I’ve liked sunline.

For chatter baits I don’t use less than 17 lb flouro.

If it's the visibility thing, don't sweat it. It doesn't matter.

Leader only on a spinning reel

10 lb braid backer, 4-6' 20lb flouro leader.

Those are reaction strike baits, you don't need complete stealth on them.

I fish almost exclusively with spinning reels...mostly freshwater, but a couple of wonderful times per year I get to go chase reds and trout.

For the sake of ease and efficiency, I've been considering spooling everything with braid and just changing the leaders when I need to go from 6 to 10 to 20 or whatever....