Oh boy, playing RIFTS as my first go as a GM (aka DM) was how I learned to play by the rule of cool and come up with challenges/stories that weren't directly dependent on character power levels. So much fun to be had with a mix of MDC and SDC characters, dimension hopping, and I also loved reading the expansion books for the over the top flavor text and inspiration.

Tried out other games to reduce complexity but still kept at least one of the expansion books for inspiration.