too old to improve
One is never too old to improve; one is, however, often too old to be honest with oneself and to admit that it takes hard work!|
The hardest thing is to return to the basics and fix them - the easiest thing is to try and fix the basics for 20 minutes and then to fall back into the old habits that ignored the basics and led to whatever problems you have.
You should definitely get a teacher - but make sure they are a performer too, as you might find someone who is just a teacher is in as big a rut as you may be. Get a teacher who will stretch you, who will be blunt but constructive. Don't get someone who tells you how good you are as a starting point.
Be realistic - you might not ever be the next Maurice Andre, Simon Lenton or Angela Whelan, but you can always improve on what you do have.
Ignore your strengths; improve your weaknesses; listen to the best players playing the best music and imitate them; develop all round as a musician; don't expect it to happen overnight; do expect something in a month or so, so long as you ARE honest; don't give up on yourself; don't compromise; Never say "never"!
Enjoy getting better.