The clicky sound could be coming from the pieces sticking to the lube at certain points, which in that case you just need to break it in a bit more. Another possibility is the GES nuts rubbing against the pieces, which can be solved by dropping some lube under the GES nuts.
I think the 6th generation will be very similar to the current mechanisms, but the consumers will be able to change the specs, such as magnet strength, and spring elasticity, kind of like what GAN is doing right now.
Lubing the pieces don't make that much of a difference, but lubing the core really helps. If the cube doesn't have a washer, the core can wear out quickly, because the spring is scratching the plastic.
Probably the old shengshou 3x3 that are oversold on amazon
https://www.amazon.ca/ShengShou-3x3x3-Puzzle-Cube-Black/dp/B004UTTXJG/ref=sr_1_4?ie=UTF8&qid=1521987754&sr=8-4&keywords=shengshou
They probably have it in stock but they are not receiving any more from GAN for now. Big cubing stores, such as SCS and theCubicle both don't have any in stock.