If you go to AMG's site and look at the Ship Points document, you'll notice we have squad points for each pilot whether they're a normal pilot or Standard Loadout. For example, Darth Vader in the TIE Advanced x1, in the TIE/D Defender, and two Standard Loadout TIE Advanced x1s (Battle of Yavin and Starter Squad). If you go to YASB you'll see those same pilots with their costs.
So Darth Vader costs you 6, 7, or 9 of your 20 squad points. Standard Loadout costs are on the exact same scale as normal pilots.
If I remember right, Quick Build fleets are meant to add up to 8 thread in a standard-sized game (8 threat is equivalent to 2.0 edition's 200 points, or 2.5 edition's 20 points), and that would scale up an Epic game.
The only relationship we can go on is ratio of pilot cost to total squad size. So Darth Vader at 6/20, 7/20, or 9/20 points, a ratio of .3 - .45 of a squad. Both of his quick builds are the 6-pointers, so a .3 ratio. In quick builds, Vader is 4 our of 8 threat, so .5 of a quickbuild squad.
That might help you merge quickbuilds with normal squads (including the SL cards), but it'll be difficult because quickbuilds are entirely their own thing and are balanced and costed against one another and not against anything else.
I hope this at least gives you a starting point!