Lesson 14: Look everywhere for inspiration. Whatever inspires you (gaming material, or not), incorporate it into your idea mill.
Absolutely! For my undersea campaign I draw inspiration from reference books, documentaries on Discovery and NatGeo, and a plethora of websites like deepseanews.com, underwatertimes.com, and montereybayaquarium.org. I also keep saltwater aquariums from which I get loads of ideas. I’ll turn a goblin shark into a sea goblin, bubblegum coral into a forest of branching corals, and a tube worm into a water dwarf in a heartbeat.
I am one of those time-strapped DMs to whom you are referring. Offline I am married and have seven kids, my job, and a hobby farm to tend to. My last face-to-face game was in 1995 but I have been running play-by-post and chat-based games since then. My next game may very well use roll20.
I am fortunate not to have any rules lawyers in my game, as I tend to run things loosey-goosey, with an emphasis on story over stats. If the players want to spend the entire session chatting with NPCs, that works just fine for me.