IMO it depends on your fishing environment. Does your fishery have a lot of vegetations, brushes, laydowns,  or mostly just open water and hard bottoms? To me, mostly hard bottoms, rarely some vegetations and laydowns, so I always use a fluoro leader for abrasion resistance. But on the braid itself, I only use 20~30lbs. 
Another benefit of 20lb braid, is that you can also use it on spinning reels. It may not be ideal, but will do. 

30# for me.  That's what most of my rods are spooled with.  In stained water, you usually can get away with no leader.  It's strong enough to rip through grass, assuming it's not super thick, and thick enough to not dig too deeply into your spool.  It's thin enough to cast well.  It's just a good all-around size.  

Though with braid, there's not much difference between 30# and 40#.  So either would probably work just as well as the other, in reality.  

 

10-20# would probably be better if you're talking about spinning reels.  If you want to do both spinning and baitcasting with the same line, I'd probably go with 20-30#.

From your choices, I'd get the 40# braid, though that would be a lifetime worth for me.  That 3000 yd. spool better be about as cheap as a 300 yd. spool, because that's all I'd need for several seasons.

I use 30lb for most of medium-heavy fishing from Jig, Frog and topwater equally only one reel, the rest 10 I use mono/copolymer. This does not include shallow spool reel and spinning. I tried cheap 40lb braid once and I feel it bowl too much and effect both sensitive and bait movements.