Who has the most spells is not what would decide who does best, it's who knows how to use their spells to the best effect that will always come out on top...
BS.
Sorry, but if the game is based around magic, and you can't start out with
stronger magic, the one who knows more different spells is going to have an enormous advantage over the one who knows only a few.
Yes, you can be somewhat clever about how you use spells, but the system is specifically designed so that you can't, for instance, use a Fireball to start the trees on fire to send up a plume of smoke to signal someone. Fireball, being a Harm spell,
must be used to hurt someone.
So even if you're very clever, your options are pretty limited.
Also, it is right that the people who have been around longer will be the stronger ones, but then it's down to those new to magic to put in the effort to learn things for themselves, or find someone to teach them...
I think the problem here isn't just that someone who comes along later will have fewer spells because it's a younger character. The problem is that the people here right now have the chance to
research lots of basic spells, spells that are simple and obvious, but that haven't been laid out by the GMs from the start. They get to make them up, and then their characters know them.
When people come along later, they will not be able to research these basic spells, because once one person has created Fireball,
no one else can ever learn a Fireball spell except from them! (or, obviously, in a chain leading back to them)
So people here now get to boost their stock of useful
starting spells by some arbitrary amount, a boost which the later people will not have access to.