I was considering splitting language skills into:
Language (speak)
Alphabet (write)
So, for example, you might have English 8 ranks, French 6 ranks, German 1 rank and Latin Alphabet 4 ranks, giving you English S8 R4, French S6 R4 & German S1 R1.
In designing a new campaign world, I'd also be inclined to have mandatory specialisation, and have different types of Elvish as dialects of a common Elvish language for example - so, in Middle Earth, a Noldor might have Elvish 4 ranks, but that would count as 8 ranks for the Quenyan dialect and 4 for Sindarin. Not so sure about that specific example actually, but as a principle it allows you to differentiate languages whilst having a good common level of understanding and fewer overall language skills.