Yeah, I don't let the sinker run up to the main line....I out a stop on the leader so it stops short of the swivel...If the bait/hook is smaller, the shark is going to eat it. If the bait is bigger and he wants it, he'll come back for it. You can only do so much with castable leaders. For kayak'd baits, you can have a much bigger section of leader that can "slide" between stops since you can make the leaders much longer.
For the ray, yeah, a wing, or center section or, we used to rig up 2 to 3 pounders with 2 circle hooks and them threaded/zipped tied in a good orientation.
Some guys going for the big boys from the beach (10-14' makos, tigers and hammerheads) use 10-15# tunas, jacks, cow nose rays....whatever big stuff they can get a hold of....those guys have full stand up harnesses, broomstick rods, 1500 yds of 80-100# test braid....and are prepared to do battle for a couple hours if needed...their reels cost more than some people's cars!
I'll try and take a pic of one of my cast leaders if I get the chance. I put a float on some of mine too, about a foot up from the hook, to try and keep the bait off the bottom to make it last longer with crabs out there. I use a rattlin' cork and it doesn't seem to bother the sharks at all.