This combination of a blazer and beige chinos couldn't possibly come across as anything other than devastatingly dapper and casually sleek. Add dark purple leather loafers to your outfit to change things up a bit. This pairing proves that dressing appropriately for your age and looking stylish are not mutually exclusive things.
For an ensemble that's very straightforward but can be smartened up or dressed down in a great deal of different ways, consider wearing a blazer and beige chinos. A pair of navy suede double monks easily amps up the style factor of any look. This combo is probably exactly what you're looking for as a mature gentleman.