What is confusing you? Try them out - you should get a good amount of foam from each of them if you have a high enough concentration of active matter.
CDEA is a personal choice - it shifts the salt curve so you typically require less salt than without it to thicken the mixture.
The amount of foam you produce might also depend on your other ingredients, glycerine typically kills foam and viscosity (you’ll see that mentioned a lot here) so try removing that (if you’re using it) and see what effect it has.
As for economic pricing, that’ll all depend on where you’re based and how much you can buy x amount for. It might be more expensive for me to buy SLES than for you, so I’d be less inclined to buy SLES.
For what it’s worth, my mixture is 4:1 SLES:CAPB with a small amount of CDEA added. I’d started with around 5% glycerine but that gave hugely inconsistent results so dropped to 2% (in theory could drop further) and added 0.1% Polyquat-7 for slip and that’s working nicely for me. For small quantities (50mL flip caps) I’m sticking around 0.9% of a 10% NaCl solution for thickening, and for larger amounts in pumps I’m doubling that. Working consistently despite trying with a variety of essential oils for fragrance.
In short: Have a play around and see what you come up with, and don’t be afraid to compare costs or look at bulk prices at this stage.