I assume that the vast majority of wannabes wish to fly in order to earn a living
Nonononononoooooooooo!!!! I always wanted to fly so I could impress the chicks with "I'm a pilot, ya know" speak. Now that's something worth investing a couple-of-ten-thousands-quids. Becoming a jet captain by the age of 25 is nice but it's your ability to squander away a healthy sum of money is what makes you more attractive to opposite (you can make that same or both, depending on your preference) sex.
Of course, I've never self-sponsored and now I'm flying for living, but it's just a case of bad luck.
Olof, seven years after geting fATPL, I still haven't found better way to find out what would suit me than old fashioned trial and error. That might just be me, but it seems that wandering around and asking questions only brings in more confusion. On the matter of paying for rating, methinks that the most sensible suggestion is don't pay if you don't have your job guaranteed, but then most companies that would give you job guarantee are the ones who prefer bonding so not much help from me here either. Whatever you do, there's no reason not to enjoy it while you're doing it. Heck, while I still have the dream about becoming B777 capt, flying as tprop F/O is loads of fun and if I could make a decent living out of it, I'd do it till retirement.
Many happy ldgs in your career!