The character boost available in World of Warcraft is inherently flawed, and broken. The main reason it so, is that it differentiates between the fresh new characters, and the "veteran" characters that are above level 60. I would like to make it clear that I do not think the problem of the character boost is its existence. I do have a problem with its ridiculous price, but as it does not affect me directly, I do not particularly care for it.
So, what is then the real issue with the character boost? We do get one boost for free when we buy Warlords of Draenor after all. Well, if you buy Warlords of Draenor chance is that you are already a veteran player. Thus the premise that if you want your character to have the primary professions leveled up as well is silly. There is no difference between the character that is level 1 and character that is level 65 when you have a couple of characters at max level already.
I will admit that I do not like leveling professions. I do it only on my main at the bigining of every expansion. It used to be useful, but nowadays there really is no need for it if you are engineer. The profession itself is just a major gold sink and I have no will or intention to change it at this point to something more "profitable". Thus investing a character boost in my Warrior that is somewhere in his twenties seemed a prudent idea before we found out that in order to get profession leveled up as well, you need to use the boost on a character above level 60.
Now, it is quite easy to level up to 60 these days. Especially through dungeons as a tank clad in all the heirlooms imaginable. But still, if the leveling up is required to make the most of the character boost, it is meaningless. There should be other ways of encouraging leveling up and exploring the old world. Like introducing the new race/class combinations.
I know some people would use a race change and be done with it, but those same people probably have enough money to buy character boost and not think twice about it. Most of us I would like to believe would actually enjoy leveling up a new character of a new combination. Maybe not all, but it would bring a new life to low-level content. Blood Elf and Human Druids, Forsaken, Worgen, Troll and Night Elf Paladins, Night Elf Warlocks, Gnome Hunters,
This is the way of how you improve the low-level population, if that is the problem. Not the arbitrary restrictions and gating systems that just limit the players. They could introduce the subraces as well in order to boost the low-level population. Mag'har, Forest Trolls, Dark Iron and Wildhammer Dwarves, Elven Forsaken, Taunka, Leper Gnomes, Gilnean Humans, Broken Draenei. They are all viable and well established options in the game.
Character boost as I see it is meant to be used to catch up with your friends, or to jump right into the action if you are starting fresh on a new realm. I do not think that need of leveling a couple of professions is helping this cause. It is deterrent, and is forcing you in a way to level up a character where you already have foothold and can support it. I am lucky enough that most of my characters are now all on the same grand realm since the merge, because there is no real incentive to start fresh on a new realm with the current character boost.