If it helps, I've just had a VAGsport resonator delete fitted to my
Cupra 300 DSG. I had the same issue as you in that I wanted a better exhaust note.
The resonator delete pipe cost £150, and fitting took half an hour and cost me £40.
As has been said before, I don't think that changing the tips will make any significant difference. Unless you wanted to fork out for a full exhaust, I think you could do a lot worse than getting a resonator delete for yours. The good thing is that it's fully reversible too, so if you don't like it (or if you need to hand the car back), you can simply unbolt it and bolt the resonated mid section back in.
I've attached a video below which gives an indication of how it sounds on a
Cupra from a cold(ish) start. It may not sound the same on the FR, but it'll sound better than stock that's for sure..!
https://imgur.com/a/22zByIV