When I read that the thousand sons start with +5 wp and fellowship I took that to mean that they got a free +5.

One of my players saw that and thought that they were just getting a free characteristic advancement.

My view would mean that he'd have a WP cap five higher than any other sorcerer (given same base roll)

Thoughts? comments?

Yeah ... it's an increase to the base. It's a Racial/Homeworld modifier, essentially.

What caught my attention to was that no basic class of marines have a stat bonus. Looking again normal humans have the bonuses on every class including a +/+3. So yeah i'm sticking with my initial ruling unless someone can give good logic otherwise?

There's not really any "good logic"; there's RAW, and by RAW, Javcs is correct. It's an increase to the base, it's not an Advancement that is part of the starting package.

That being said, it's your game, and Advanced Archetypes are stupid. Whatever you can do to condense the amount of speeding dumb gets approval from me.