Bike Gearing

I own a 2008 Quintano Roo Kilo 52cm

The cranks are Gosamer FSA
The big ring is 53
The small ring is 39
The big ring says 53/39 showing both sizes
the small ring says 39T –s10 I am not sure what the s10 is
Both rings say 130 mm

The rear gearing are 25 on the biggest gear
The rear gearing are 12 on the smallest gear
Total of 10 rear gears

I want to modify my gearing to focus more on the upper gears and not have as many lower gears. I want more push for my pedal. I have researched upping the big rings up maybe 2-3 teeth, but I have also heard I could change out my rear cassette and get the same results.

Here is the just of where I am at. I have been passed by someone of similar size and build with very similar cadence but they quickly passed me. I have more strength in my legs but at a certain point the gears seem to be hindering me.

Any ideas of a way I can resolve my issue without breaking the bank. I would like to say I am a major biker and know all the ins and outs of what works and what won’t but I am really not that knowledgeable.

Can any of you help?

Thanks,
Ray