Hi there. I have an orc warrior on one server (only horde char) and was wondering which profession combo would benefit it the most (usefulness and profitability) considering that it won't have support from any alts.
My warriors are always mining/blacksmithing. Profitability rises and falls depending on expac and what the devs have done with it. But you can always make yourself gear and of every profession in the game, i find them to be the most enjoyable to level up and work on. There's something very relaxing to me about putting on some music and just mindlessly farming ore - though it's a lot more fun with flying, but that's another thread.
I'll always have Engineering on my main because it's the profession that provides by far the most utility. Teleporters, Jeeves, mailbox, rocket boosts etc are really useful to have on your main, especially if you spend a lot of time doing retro raids and stuff.
Enchanting is a good second profession to have on your main since you'll be getting tons of BoP stuff to disenchant and it's nice to be able to enchant drops immediately.
My suggestion, if you are looking into Legion, is Mining+one. Enchanting vs Blacksmithing vs Engineering is probably the bigger question as #2. Reason behind at least 1 gathering is because, with the departure from (FINALLY) our garrison to our "class order hall," mining and herbalism won't have the same resource income, so they will be more profitable for a while. And, the benefits from professions have supposedly been removed (no stat bonus, engineer's perks are items everyone can buy and have limited in combat usage), so it should be whatever works for you. Enchanting will be self sufficient (quest/kill mobs, d/e items, use or sell mats, sell enchants if used, profit), and both Blacksmithing and Engineering can utilize mining for gearing.