I've always thought of ED as being quite easy to pick up but then I was a vet of the previous games. Still, its got to be more accessible than the likes of EvE. That said, as its expanded over time there is a lot more to it and where I've gotten used to the features incrementally I can see how it might intimidate some particuarly at first.
Putting work into an improved in game tutorial system would come at the cost of actual content. Maybe Frontier could make some more tutorial videos instead..? Although, there are quite a lot of player created ones on youtube already.
I am curious though, how many people have read the game manual?