I have a few 70s and I am going with prot pally + mage + 3 shammies. I've already leveled up to 350/375 profs on all of them:

pally = mining/alchemy
mage = tailor/enchant
shamans = skinning, LW, mining, JC, herbalism, inscription

The only profs I am missing are blacksmithing (all mats saved, gonna use for a deathknight later) and engineering, which I have on a 70 warr I will level later.

Mining is gonna be a big money maker, there is a xmute on 20 hour cooldown for a bar that is used heavily by BSs and engineers and will be in very tight supply.

In TBC each prof had very good high end BOP items - weps for BSs, entire sets for tailors, decent items for LWs, etc. In WOTLK profs get self-buffs like 2 extra gem sockets for BSs or ring enchants for enchanters, but almost all crafted items are BoE and may not be "the best". Frankly having 5 miners may be the best money maker, if you have your heart set on 5 mechanohogs or mammoths.