A problem that may occur is that a customer does not want "non-professionals" working on their aircraft!
This has happened a few times with modern apprentices in MRO's where the customer wanted work re-certified or would not pay for the Apprentices man-hours.
A snag I hit once was how to give an approval to someone who did not have any recognised basic training? In that company's quality system I couldn't give the subject a Workshop approval - I dont know how that would work under EASA's Pt 66?
Other than that I cannot see any problem with the self-taught route.
Good Luck AA - We need keen people like you to enter the industry.