I think it would make sense and be thematic for divine casters to get Tongues (for the spoken word), arcane casters to get Comprehend Languages (for the written word), and occult casters to get both.
If they implement shorter 4E style rituals like I and others have advocated, a good ritual accessible to everyone would be one that gave the caster / participants a single specific language. They could then read and write and speak and understand that one language temporarily. It would be a good bridge.