I speak of experience here! I have a Twingo GT (various posts about it on here) and like you, was worried that the firmer suspension might be a bit too firm for daily use on our real roads, which as we know are generally poor.
However, I was pleasantly surprised that compared to the previous car, which was a very up market Laguna coupe "cruiser", whose suspension really was too hard and spoiled what was a gorgeous car to look at, I found that even on the Twingo GT, the suspension wasn't as crashy and hard.
But I do have a thing about unnecessary "blingy fashion accessory wheels" with lower profile tyres, such as the 17" ones on our GTs. And likewise I agree that most modern car suspensions are too firm.
So to help smooth things out, I bought a set of 15" wheels from an online supplier (Wheelbase Alloys in Oldham, but others are available) Have a read of the thread I put up about them here. (Link below hopefully)
Even if I say so myself, I think they look pretty good. The other advantage is that 15" tyres are cheaper than the 17" ones. Also, come the time that I part exchange the GT, I will put the original wheels and tyres back on it, which will be pleasantly undamaged!
They have softened the ride slightly and are also a little quieter.
One tip though - don't forget to get some Renault TPMS (tyre pressure monitor valves) fitted to the wheels before they put the tyres on, otherwise your tyre pressure warning lights will light up all the time.
Hope this helps.