For yourself, you bought a bike that is suited to leisurely reiding and it sounds like you want to be a bit more aggressive and aerodynamic. It might not be too late to take it back, but if not, you can do a bit to speed it up.
Just like your kids you can opt for slicker, skinnier tires. Also, for efficient road riding the handlebars should be about the same height as the seat to make you more aerodynamic. There are two possible ways to lower the handlebars. The stem might be lowered a bit in the steering tube if it's not already at the lowest height; and, you have an adjustable stem that allows you to swing the handlebars forward and down. The first choice is preferable, because the second choice might make the handlebars uncomfortably far forward to reach.
It may seen counterintuitive, but when you lower the handlebars, you might need to slide your seat slightly backwards on it's rails. That puts more of the weight of your torso on your legs than on your wrists.
Hope some of these ideas help.