To Krellen: Hmm, I understand what you mean, but I think of it in another way. The reason you can't have more ranks in reading/writing than in speaking is that you have to know what a word understands before you can use it in writing. This system is also designed for a setting where the skill in reading and writing isn't that common, and people who can read or write are looked up to.

You might want to ignore the skill-points in reading/writing and instead add a special advantage called "literacy". Cost would depend on the setting (in mine it would probably be around 200 xp), and must be bought separately for each language. Once you have bought this advantage, you can automatically read/write at the same rank as you can speak.

In a setting such as Greyhawk, where literacy is the norm, you may go the other way around, and make illiteracy a disadvantage, giving you 100 xp or so.

Do you like any of these better, or didn't I fully understand your question?