We need to document some advanced program flows (far more complex than just the revenue modeler). Of course, I've used Visio ... but am hoping there's something leaner and more modern. I'm not asking anyone to do any Googling ... can do that myself. I'm just hoping someone has a personal recommendation for a tool you've used and find works well capturing interaction between programs and flows within programs. Hoping to find a "hidden gem"!
I've always found Lucid Chart to be a tool that does the trick pretty well.
draw.io works well, it's free, and you can connect it to Google Drive! They also have paid versions that connect to Jira/Confluence if you use those tools as well. https://about.draw.io/pricing/
Lucid Chart all the way. So much nicer to use than Visio, and you can upload custom icons (I think on the paid version, but it isn't expensive).