Fast is super fun IMO. There’s some good downhills where I live and it’s possible to get up around 80kph (50mph). Once you start going up over 30mph aero matters a lot. Staying low and tight gets you faster speeds. Working on a good aero tuck(if you can really call it that for us Clydes
) will get you speed. Breaking that position to pedal can sometimes slow you down. On the pedaling side, laying down power at those higher speeds and higher cadences is something you need to work on. Do you have a cadence meter on your bike? If not one could be a huge benefit to you. Ride down hills in a small gear from time to time a really rev it out, like 120+rpm. Also do it on the flats occasionally too. What you want to work on is having the feeling of pushing on the pedals at high revs rather than the feeling of chasing the pedals around with no pressure. Working on that will get you faster at speed when you start revving out that big gear. Work at it and you will get better at it.
I’d only gotten back into riding for about a year before I got into low level road racing and track racing soon after. Track is where I developed my spin ability, and it took a while for it to develop, so don’t get disheartened and think it will happen overnight. But work at it and it will come