Do you want a bike with flat or drop handlebars? Speed is often down to aerodynamics as much as it is your legs, so a drop bar bike is probably the way to go.
There are diminishing returns when it comes to group sets. Shimano 105 is a nice combination of value and performance --any Ultegra & Dura Ace shifts the same, but is lighter and far more expensive.
Frames are a little more complicated. A carbon frame is comfortable but fragile for year-round use. A small crack can render the frame worthless. Aluminium can be a little harsh, but Cannondale has been making great strides in that department. Steel is excellent. A nice feel, smooth, and not too expensive. Genesis has some great steel all-rounders to choose from. The Equilibrium would be my pick.
So, pick the frame you like and go for Shimano 105 gears. However…
Best go along to a bike shop to make sure you are buying the right size. If your bike doesn’t fit you, it’ll be horrible to ride and a complete waste of money.