... I believe that new and better lubricants are now being made such as Superlube synthetic grease and oil.
I'd agree and therefore the bally documentation on lubrication won't matter. However, this is like motor oil in cars ... ask 20 people and get 40 different answers with enough "except when"s tossed in to make ya want to go back to 1940's and use the recommendation then - vaseline.
while heavy grease on significant metal-on-metal pressure points like the release pawls, windup gears, and handle gears will protect from excessive wear, the machines aren't being used 24x7 and having grease harden isn't worth the trouble imho.
fwiw, when I disassemble stuff I just use isopropyl alcohol to clean all the parts, tri-flow lubrication with teflon (squeeze bottle) for metal-on-metal parts, clock gears and the reel needle bearings, nothing on plastic-on-metal parts, and nu-trol contact cleaner on the contact plates (basically a pure mineral oil).
cleaning contact plates (reel wiper boards, payout counter, stepper units) - isopropyl and a scrub pad. At the Pacific Pinball Museum we use maroon 3M pads, but the common green kitchen scrub pad is fine. Anything that won't leave scratches or shed, so I wouldn't use sandpaper. I clean then spray on a little nu-trol and smear it around with my finger.
see
https://bingo.cdyn.com/techno/overhaul/magic_ring/chemicals.html for pics of products.
occasionally if bored I'll use a synthetic grease on the release pawls.
if you have sticky lube in the mechanism, spray solvents like brake cleaner, carb cleaner, mass airflow sensor cleaner, etc. may shoot it out better than just brushing alcohol and wiggling things if you don't want to disassemble. Just keep away from paper labels and reel strips, and make sure the solvent evaporates away before making sparks.
super-lube will definitely work, but when using on contact plates the key is really thin. Goop it on and it will make wiper movement sluggish. If you can see it, it's too thick :-)
thin amount of super lube on the piston cup seal will work.
wrt the cup seals themselves, I put someone's writeup here:
https://bingo.cdyn.com/slots/bally_info/Bally%20Piston%20Cup%20Replacement.pdfpoke around in
https://bingo.cdyn.com/slots/ for more info if you're bored.