I would disagree on that, that it is not balanced. In my opinion, the way that it is currently set up is the environment that creates an unbalance. If you take a brand new Sorcerer, and put him against a brand new Conjurer, that Conjurer is heavily favored Karmically, because he was allowed to spend his Karma on other pursuits, whereas the Sorcerer gimps himself by spending his Chargen Karma on spells. Permitting free spells would put them on the level playing field. Obviously, play testing is required, but between the two, I would say that it is more equitable to give Sorcerers and Alchemists something.
To clarify my point, let's move away from comparing Sorcerers/Alchemists to Conjurers, and instead compare them to full Magicians. Let's give Magician A and Sorcerer B both a Magic Priority of B, and under my house rule, they are both afforded free spells. All other Priorities are identical between the two. As per the table on pg 65, it looks like the Sorcerer might be coming out ahead, due to them receiving a nice 1 Magic pt bonus and a 4 pt Sorcery Skill Group, instead of just two Rating 4 Skills. But are these two advantages equitable to the utility of Astral Projection, something that the Sorcerer will never get? Not to mention that the Magician is not barred from summoning spirits or artificing, even if he chose not to put any points into it at chargen. Assuming that the two characters were built exactly the same way, regarding skill, attributes, spells, etc, the ONLY differences between the two will be that the Sorcerer has 1 extra point of Magic, and the bonus of a Skill Group, while the Magician can Astrally Project straight out of the blocks, and will be able to summon and enchant at his leisure down the line. To me, these two are equitable. The Magician is supposed to start out weaker, and snowball as they go along.
Returning to the concept of whether a Sorcerer or Alchemist would be balanced against a Conjurer if given free spells, I think this is entirely fair. Again, let's assume you make two characters exactly the same, except one is a Sorcerer and the other is a Conjurer. It would have to be explained to me how this is unbalanced. Sure, if both characters start just facing each other and start blasting one another, the Sorcerer will probably come ahead, as the Conjurer would have to summon a spirit to make use of his talents, whereas a Sorcerer could instantly blast him with a Manaball. But in terms of all around power, including fighting strength, utility, and not to forget things such as the ability to bind multiple spirits and employ them all at once, I can't imagine how a Sorcerer has an unfair advantage, simply because he got more stuff to start.
But, again, my main assertion is that, in my own opinion, giving free spells to Sorcerers and Enchanters is a LOT more fair than giving them nothing, in comparison to Conjurers.