I usually stay in Le Port area of Nice fairly close to Place Garibaldi, so these recommendations are in that area. The tram line runs to Place Garibaldi, so this area is easy to reach. My favorite place in Nice is Alto Restaurant, 21 rue Barla. It is owned by an Italian family that has been in Nice a couple of generations. Excellent value, but a very high level of cooking. They offer wonderful small plates that are the centerpiece of their menu. They offer main courses and pizza. After 5 trips to Nice, it is still my go-to.
In the same neighborhood, L'Uzine, 18 rue Francois Guisol, is great for a more intimate meal. Their lamb dishes are especially remarkable. I would recommend reservations for both places even during the week. Especially Alto. In the off season, you might get a walk-in table but I wouldn't count on it. My final favorite is Chez Pipo, 13 rue Bavastro, THE place for socca (chickpea pancakes) and other apps. It has been in Nice forever and is almost always packed. Just relax and plan to wait a little. Lunch is a good option if you don't like to wait. Both L'Uzine and Chez Pipo have outside tables (well, Alto has one, but mostly just a smoking area), but in France that means lots of cigarette smoke.
I'm in Nice now, so it's nice with some recommendations! Any tips on where to get fish stews and seafood, that is good value?
I checked my restaurant list for Nice. This restaurant is quite close to the tram route and I think not far off the Promenade and Place Massena. A cooking teacher from Nice, Rosa Jackson, recommended it but I have never actually been there. Ceviche. Is easy to find. Enjoy Nice!