There are many options. New clipless pedals, bike fit, new saddle, tires, wheelset, better diet...

Clipless pedals should be the first thing you get. After that I would go with some quality tires that have a lower rolling resistance and are stickier in the corners. A new saddle helps out a lot too because it's a lot easier to bike further and harder when you're more comfortable.

People say a bike fit will help, however I feel like if you read up some sources and do some measurements yourself you can get it pretty close and save some money.

I've heard mixed results on a new wheelset.

Oh and Sora components are pretty low, you may want to consider all Tiagra or even 105 (pricey).