Marry a turtleneck with a grey suit if you're aiming for a neat, smart ensemble. And if you need to instantly tone down your outfit with a pair of shoes, introduce a pair of tan athletic shoes to the mix. So if you're looking for a great but also age-appropriate pairing, you found it.
This combination of a turtleneck and a grey wool suit couldn't possibly come across as anything other than incredibly dapper and refined. Tan athletic shoes can immediately play down an all-too-classic look. A wonderful example for anyone who wonders how to dress as a mature man.