Was going to say when I started reading this thread that mechanical engineering was one good possible choice and one day have your own business , accounting wouldn't hurt with that either .
When I did the bigger brakes and supercharger on the monaro got it engineered , very simple job for him but gives me peace of mind and no problems if you're ever pulled over and really want to question it.
Anyway this engineers business was obviously engineering but also paint and panel work, full vehicle restorations , had some really old cars in there through to mustags , 70s fords, monaro 70s one. Can see the attraction, one stop shop, especially if you're getting it modified as well .
While some say don't mix work with hobbies , every one's different and what works for some doesn't for others.
One thing is for sure if you end up with your own business it especially helps if you have plenty of passion for what you're doing .
With the mechanical engineering could also end up in aviation although the number of opportunities would be more limited .
Have to say I've been pretty lucky, worked for my father for a year when I left school but always wanted to get into aviation and got a apprenticeship the following year. 37 years and 2 redundancies later still doing pretty much the same thing and enjoying it.
Variety helps, Oh and 4 10 hour days so 3 day weekend every weekend.