This is actually really quite interesting. One thing I would ask is, since the ranks have different skill point requirements, can characters carry over skill points from level to level? Or do they just automatically invest them and just don't gain any benefit until they hit the skill point number that gets them up a rank?

Like, say I have a Rogue. At first level, he has 8 active skills that he gains apprentice rank in, or one skill that he is an expert in. But let's just go with the 8 skills with the apprentice rank. When he gains a level, he has another 8 skill points. He can either: Make 4 of those Journeyman, one expert and one journeyman (with a point left over). That is assuming that you can only spend skill points in order to purchase ranks. If he can just invest them, he gets 8 skills at first level at apprentice rank, and then at 3rd level all 8 become journeyman, and then at 6th level they all become expert, at 11th level they become master skills, and at 19th level they all become superhuman. Which system do you think fits your vision best?

In addition, how do you quantify a Task as being at a certain rank? Are you just going to go through all of them and do it? Or should the DM try to do it on the fly?

Do the skill points give any actual bonuses besides going up a rank? Is that it?