I don't pretend to know much about trolling for lakers... but I do believe that snagging bottom now and then is pretty much inevitable. Unless you find those spots that are fairly level or are all sand, you're gonna lose some gear if you drag for lakers a lot.
A lot of the guys that troll right on bottom use leadcore (lots of it- like 8-10 colors) going real slow and they use live bait... Cost wise, I'd rather replace a single/treble hook rig and a shiner than $5 lures.
If you feel the need to drag with downrigger balls, I would think the pancake weights would snag less often??? Or maybe put your rigger ball close to bottom and run a color of lead off that to make up the difference... that would keep you from losing rigger balls and maybe the downrigger itself if it hooks too tight and you can't cut the cable in time.
Just my thoughts... I'm sure you'll get a better answer from someone else.
Have fun