"Randomize seams" uhh no, design parts with seams in mind if they are critical. I often add a small 0.3mm double chamfer "zipper" on a surface because it will accommodate the inconsistency and reduce it by forcing the root inside the body. I've made my own infill structures and patterns lately too.

I like to use petroleum jelly as a lubricant. Mainly because it's non-toxic (so can be used on toys for children) and is very readily available. Requires some working-in as it will be sticky at first. Too much will gum things up until its been worked in. What's really good is its initial stickiness ensures you get a good coating on any gears in direct contact with each other