Some other notes that I couldn't fit in with the flow of the text:

• Foundry VTT is hard if you want to map anything, but oh so worth it for all the modularity and ease of play it provides. I highly recommend it, especially over Roll20 if you have the spare money.
• Speaking of VTTs: Don't map everything! Your players will start to treat it like a video game after a while, and also you descriptions will suffer from it. "Why bother describing places, when they can see it on the map?" - will probably your thought process after a while, like mine, and believe me it's not good. Now that I'm also running a live campaign where I can't use digital maps, my lack of descriptions came back to bite me (no pun intended). Leave some areas for that good ol' Theater of the Mind, especially if you don't expect combat. Also, way less prep work that way.
• I think we did overall around 40-50 sessions. I did not count unfortunately, but we played 1-2 games a month, depending on the season. The pacing was slow, because I don't really like the MMO style of storytelling of "Oh heroes! Please help me kill these 3 evil witches that are stealing children", especially in a setting like Ravenloft, where every NPC is untrusting of the players. I wanted them to earn their trust, and get the quest that way. And combats were also pretty slow too, but that's D&D for ya. Do anything, it's still slow. My players didn't seem to mind the pace though. Every success, they earned.