1. Wash pads should be maintained like a pet with long hair. Regular washes and brushed out.
2. Washing MF towels is more about washing towels soiled to similar levels. The cleanest MFs washed together first, followed by dirtier, followed by dirtiest. I am talking real dirt, dust, scum, etc. If a towel is only soiled with product, it can be washed with other, clean MFs. Just make sure to use enough soap, and dry on low heat or no heat. I pull my MFs out of the dryer when they are *almost* dry.
5. VRT is a dressing. Best used on clean rubber, vinyl, plastic, or tires. I prefer applying it using a foam block. A little bit goes a long way. Don't saturate the surfaces with VRT. The key here is prep. Make sure these surfaces are CLEAN, and you only need a little bit to make those surfaces look great. If you apply too much VRT, buff dry with a clean MF or terry cloth towel.
You mentioned you have H20 GG. You don't have to wait to apply it. H20 is meant to be a maintenance protectant and glossifier. When you strip wash, the H20 GG comes off with it. It won't hurt a thing to apply it after a regular wash, before you do a full correction.