Former aircraft engineer known as Get a Bigger Hammer, I wasn't going to reply to the above, but.....
Moving on and growing doesn't necessarily mean you have to move from one profession to the next. New skills learned and qualifications gained (qualifications not licences) can just as easily be used to make you better, more interested and more satisfied in what you are doing now (I've done it as well). If you enjoy working on aircraft why go and design vacuum cleaners, fix computers or write software? If you really want to, you can grow in this job as much as in other walks of life.
I've worked for big airlines and small airlines. I've even worked in the family business (retail). There are loads of other jobs in the airlines that you can "grow" into other than spinning a spanner or pouring a can of oil. Be what you want to be, go where you want to go.
I certainly don't feel I have dimimishing opportunities or going down a tunnel following a pin prick of light called retirement. I've had the chance to design and redesign mods, design and manufacture test equipment, plan maintenance inputs, run maintenance inputs, be a company rep, be the voice on the end of the phone when things are turning to rat-sh.. down route, liase with manufacturers and the CAA, write engineering and quality procedures and loads more. I'm just an AMEL holder working on Mr Boeings produce, on the tools.
I agree with you, engineering is more than reading manuals and jobcards. It's also more than kicking tyres and pouring a can of oil. Ever fixed a snag that wasn't in the FIM or Trouble-shooting Manual (if you have such a luxury) and has taken three days? Didn't that use any of your creative juices? Ever been given an SB to do that is a load of bollocks and you have had to go back to the manufacturer and say "That's a load of bollocks. If we are going to this we need to do it this way." and they have come back and said "Yeah, you're right. Do it that way and we will re-write it." Or have you ever found the same problem on more than one occasion and said "If we do this .... we won't get this problem so often" and somebody has gone and done it that way? Isn't all the above creative problem solving and improving? The day this job stops having its problems to solve (engineering wise, that is) is the day I, like you, will give it up and find something that is more rewarding for me.
Don't assume the chance of a glance at the occasional half errect nipple is the sum of my ambitions - as I said that's a pert, sorry, perk. And I doubt that is the sum of Shaymey's ambitions either or he wouldn't be asking for the sage advice of so many wise men and women.
I'm sure I speak for all your ex-colleagues in aircraft engineering in wishing you every success, happiness and fulfilment in your new career.
And Shaymey, remember, it is those with the biggest axes to grind that shout the loudest.