I was in Nice a few weeks back. A disappointment of biscuits, but I liked the rest of it. We stayed on the seafront, plenty central, with the big hill up the road. Did plenty of walking and swimming in the sea. You might not want to do the latter in winter though. I preferred it to Marseilles, tbh, which is a bit more gritty, more urban than urbane. You'd be far more likely to encounter Sophia Langoustine in Nice than Marseilles. Though she might have something against bouillabaisse.
As a bonus, there were no dildo clowns in the wardrobe.