Should I buy some Materials & Sell them off at the Auction House or Buy the Trinkets, Un-Bind them, & Sell them? Which would give me more Bang fer me Buck?
118 Primal Sparks: What to do, What to do...
I think the trinkets go for 10kcr for the 5* ones.
The 3* trinkets are a good value if you like T2 lockdown and don't want to roll for UVs on your armor. Can't use any of the Krogmo trinkets in T2.
Either use the tokens to buy some material for any recipes, or buy and sell trinkets, not at the auction though, with NPC's.
Also, what's the best Material to Buy for now?
Prices fluctuate all the time. If you want to optimize it, put the token costs of each mat in a spreadsheet and then fill in the estimated auction price based on what they're selling for in the AH. Do a simple division and you get your cr/token yield.
Off the top of my head, you're probably best off looking at Monster Bones, Bushy Tails, Warp Dust and Primal Ore first, but check the prices for each mat to make sure, and try not to flood the AH with too many at once or you'll just end up driving the price down by running out of buyers.
Don't buy those trinkets to sell, ever. Much more useful trinkets (ASI, CTR, etc.) don't even sell for unbind price, and the ones you get from Brinks definitely don't either. You can always buy the trinkets and sell to a NPC, though I'm not sure how much it would fetch, but buying an expensive material and then selling it is probably your best bet. I always save mine in case I need to craft in the future, but I'm a crafting junkie.