I'm a fan of Dungeon World myself. Super simple as it uses the PbtA system and easy to teach anyone. I've had some real successes here in getting people who don't normally enjoy system games to have fun rps using it. It feels like D&D too (at least AD&D 2e with it's fluff) but isn't bogged down with much crunch at all. It's the one system for me I find generally is easier to GM too.