How to talk about improving sex with your spouse or partner

Dear Jeff and Lori,

My wife and I have been married for 17 years. We have a good marriage in that we both love and respect each other, and work well as partners in parenting and daily life. We had a great sexual connection in the early years of our marriage but over time it has become lackluster. I thought as our kids got older we would find that connection again, but they’re teenagers now and nothing has changed for the better. I don’t want to leave my marriage but I also can’t imagine spending the rest of my life feeling sexually muted. I want to grow and experiment in this area but my wife is content with occasional, routine and vanilla. I’m afraid of sounding like a stereotypical hormone driven male, but the truth is this is a big deal for me. What should I do?

Signed, Bedroom Doldrums