Weldbond is a very strong adhesive. Secret to saying fewer bad words is to pour it out and let it thicken b/f applying, then the tess won't slide as easily. I'm using it on Queen of Country, and it's driving me crazy. Best used on flat surfaces. WOW - didn't realize the redwood w/bleed through grout. Sounds like you have a solution - Kilz, if it's water-based. Otherwise, oil-based doesn't mix well w/water-based products. I found that out when I used Armorall on a wooden pedestal, then tried to mo it w/thinset. Didn't work. Anxious to see your WIPs.

what adhesive is best on metal or brass?
would you use wellbond too?

if i use kilz on the wood, do i still need to seal it with wellbond and water solution?

On the metal, I would use GEII. Weldbond w/work, but it slides so badly I'm not patient enough to wait for it to thicken b/f applying. I wouldn't think so on the sealing, but I seldom seal w/glue/water solution, unless it's raw, new wood. Like NT said I'm not an expert on anything - I experiment all the time, and am constantly learning, so go w/your instincts, and don't forget to check out on-line tutorials and books.