It's good to have be flexible, to have a wide base to build off of. But the way you think about color magic is going to have to be more focused. Although cantrips are shared by all, every color has a different process. Within a color, even spells that are very different share a certain feeling to them.

At least, that's my experience. That's why a blue mage can't really help a green mage with his spells - just the source. Our magic may be the same, but the way we channel it is entirely different.

Does that make sense?