The north is where Mauritius is easiest without a car. Grand Baie has the density of restaurants and bars; Pereybere, ten minutes up the coast, has a better public beach and a quieter evening.
What it costs
Guesthouse rooms start around 1800 rupees a night, against roughly 7000 and up for a north-coast resort. Eating out is the same either way, so the gap is close to pure saving.
Who it suits
First trips, anyone without a rental car, and anyone who wants to walk to dinner. If you want an empty beach, this is the wrong coast.