An easy question to answer as my #4 game is Digimon World (and other digimon games) which gets very low review scores. Its a game with pretty innovative gameplay and one of the best monster raising games.
For a bit more modern example is my #6 game Romance of the Three Kingdoms IX. One of the best army simulator games, even with multiple flaws that need to be set up. In fact I didn't like this game at all compared to the others in the series. But when I played it for more than 50+ hours , the game really opened up to me and I realised just how fun it could be.