I would!
Ideally you wanna stay anywhere from Le Morne (south west), through to Flic en Flac, Trou-aux-Biches and Grand Baie. Skipping the section between Flic and Trou-aux-Biches. So the west coast. On the other side Blue Bay is spectacular. And a day’s visit to Ile aux Cerfs to see the amazing beach is semi-worthwhile.
Hiring a car, that’s a difficult one. They’re not expensive, but really Mauritius is all about the beach… wake up, breakfast at hotel, beach, maybe some lunch, then dinner and nightly entertainment provided by the resort (most resorts are half board). Wash rinse and repeat. If you’re going out exploring, you’d probably want to do it every second or third day maybe.
That said, driving is easy, the roads are good. I’d get 100% insurance excess waiver - at the counter - so you can just return the car… they can miraculously find a scratch here or there! Your travel insurance may cover the excess, but you have to pay first, then claim. Much better for peace of mind to just hand over the keys and go catch your flight!
Port Louis is nothing worth while visiting, save for maybe a short walk through the historic town centre. It’s about a 39 minute exercise. The redeveloped waterfront with its shops is disappointing, A bit like Docklands in Melbourne… dead. And shoos that no one really wants anything from.