I'll typically buy cards that are < 66% of my crafting cost in unlimited quantities. If I have high stocks, i'll try to repost at 1/8 of the deck's market rate. I don't care if someone is resetting the market because i WANT sales volume and if someone is trying to a reset it's usually low enough for them to buy you out. The point here is to constantly churn your inventory and adjust down with the market.
Sky golem is all profit if you do the smart thing and run old panda farms on multiple toons. Was running 10 farms at one point till bfa launched and was upto my eyeballs in trillium and Ghost iron. Just not been doing it lately, but those 10 farms was an hour a day if that and sustained 4 crafters and alchemists though could have sustained 8 easily.
Mythic+ rewards will also go up by 30 item levels; however, during the first week of Season 2, rewards from end-of-run chests will be capped at Mythic 6 quality (item level 385), and the chest you open next week will contain Season 1 rewards if you do a Mythic+ run this week. (So, for example, if you do a Mythic 10 during the final week of Season 1, you’ll get a Season 1 item level 380 piece and 60 Residuum from your first Season 2 chest.)