If it is straight years of school, then an average person might have between 10 and 12, starting school around 5-6 and finishing around 16, so that makes sense. A holder of a Bachelor's degree in England would probably have EDU 16, a Master's EDU 19 and a PhD EDU 22.
Of course, you could have a high EDU and not have the qualification, or have the qualification and not have the EDU, depending on the life story.
In the RQ SciFi document I put together, it gave Adventurers an EDUx5% boost to their skills, but this had to be applied to a certain list of skills.
As for the LifePath idea, it looks good, but I didn't really understand it well enough to give it a full treatment. When I played Traveller, I was guided through it by experienced hands, so didn't need to understand the whole process. I only rolled up 2 Traveller PCs when I played and that was over 20 years ago. Having said that, it should b e easy enough to do. I suppose I should buy the Traveller rulebook, to see how it works properly, as the Mongoose Traveller SRD is not that complete.
I am glad that you are trying this, Layec, as you might be able to work out any issues in it.