Baldur's Gate, the first one, will always be one of my favorite Infinity games. It had the numerous npcs, of differing alignments, races, who could join your party. It was not overkill in leveling. There were many places you could visit, indoors or out in the forests. Plus there were a lot of side quests you could take on.
The only draw back was the npc's dialogues was simplistic and not complex with altering responses and replies like Baldur's Gate 2. Plus it did not have any romances.