Good advise above.
Fitting for position and posture is very personal.
If you are someone who can absorb info from reading, there are many good sources of info on the web, to help. Which are better than others? That's a hard decider which also depends greatly on your physiology....
I recommend, whatever you do to improve your riding position and posture, is to make 'changes' in small increments with some reasonable adjustment time to each change.
You're already riding quite a bit? If so, the body does become accustomed to how it's asked function currently, large scale changes could cause great discomfort and even injury.
WHat's a large scale change? in particular for saddle position setting, a change of 1 cm is quite large, I prefer and recommend changes in height or saddle fore/aft (where the seatpost clamps to the rails). of 3-4 mm at a time, and then ride for at least 5 of your regular ride routes before making another incremental change.
All done with the intent to reach a certain setting point, down the road...
Also, recommend making one change at a time, so you can evaluate the effect of just that change.
If someone (or a fitter) is wanting to make a wholesale/large change, resist and ask how best to proceed with incremental changes to meet that new position.
Give your body a chance to adapt to changes and then evaluate.
Ride On
Yuri