Haven't tried Slackware, but I thought Arch was a great intro! Still remember my first "Wait, it's fully installed now? Where's the UI??". We did have the setup

Haven't tried Slackware, but I thought Arch was a great intro! Still remember my first "Wait, it's fully installed now? Where's the UI??". We did have the setup menu at the time. Haven't gotten around doing Linux From Scratch yet, but I hear it's a good experience, from a dev perspective at least.