Generally I will level up my professions as I go. I don't spend money on them, really, except for learning new patterns, but I do try to keep them at the right level for me so I don't have to face the grind when I hit 70. Another reason I do this is because you can generally make some money out of your professions. Not much, sure, but it is enough to cover the costs of learning the patterns for most professions.
Enchanting is different. Enchanting is my bane. I want a high level enchanter, because when you start to get the really good enchants you can start to make some money at it, and you also become really helpful to your guild and friends. Sadly, since there is so little money to make from leveling it I tend to let it slip behind my leveling and have yet to get my enchanting skill much over 100 with any of my characters.
What I would like to see is enchants being made more like the glyphs and inscriptions. Namely something that the enchanter can make and put up on the auction house for someone else to buy and apply themselves. Meeting up with morons is the hardest part of selling enchants and making them into self-apply patches would help take away the need to actually meet your customer and wonder if he's ever going to put your fee in the trade window so you can accept and get going.
Also, if you could trade them over the auction house then you'd actually get to see what value most enchanters put on their enchants. The number of times I've had some bottom-feeder tell me that an enchant isn't worth the cost of the mats I am putting into it (they often claim that another enchanter did it for them for a fraction of the mats cost) is silly. I want to see if these people are right. If other enchanters reall are selling an enchant with 2g worth of mats for 20s. Mainly because I'd like to laugh at them, then slap them, then sulk off into a corner and cry.
So, yeah. I want enchanting to be made into a profession which can be done as if on a one-player game, so sue me. I just don't like dealing with the great unwashed of WoW and with every other profession I get to avoid dealing with them.