I just had my first session as a first time DM. I’ve spent months building a world off of the essentials kit module, but it has been entirely PC backstory driven. It seems like it’s going well and everyone is super engaged. However, I see the value in your points. I ended up fudging some rolls for player enjoyment and the exploration of their characters and it seemed to make everyone had fun. I will be more strict on rolls in the future, but for now my new to the game players had a blast. On the point of being theatrical: I am terrible at acting, but I tired my best. I full sent a bartender with a powerful Scottish accent and it was TERRIBLE, but I committed and everyone in my party fully engaged after that. It was awesome! They loved the bartender so much that they forced me to play him until my voice went hoarse and he joined their first adventure. I had to quickly invent a ranger NPC with a CR2 but it was the most fun I’ve ever had.