Dream sequences are a bit tricky for me since my work has a concept called "Soul Links" which can have similarities to dreams in a way but are pretty different. I can say so far I've had two dream sequences. Both have been to show an aspect of the character currently in their own way, be it Jaron's growing worry/paranoia for those he cares about being visualized by being alone and attacked by the object of those concerns or Demetri with feeling guilty about something that relates to his friend and father, but we won't go into detail.
Basically, I choose dreams when it fits for not just the scene in question "they're tired or resting somewhere" or "post a rough fight and they would reasonably be resting" and the like. I also try and see if I can add more meaning or point behind it by focusing on these two questions.
1: How does my character's dream relate to how they're feeling (oftentimes now, but could be longing for old feelings or yearning for new ones)
2: What does this dream say or show about the character's perception of the world around them.
To show this, my two examples once more.
Jaron's situation would not cut him to a point of being unable to see anyone or be around anyone, not to mention the antagonists don't seem to be after all of his group. However, in his head, the mere point of them being a threat to someone he cares about leads to the plausibility of all of them being at risk for it. Why he reasons this, there's a couple of ways you could say, and even if he doesn't exactly show the major point of it 24/7 or to the level he feels, his raw dream state I wanted to illustrate how seriously he takes something like this.
Demetri's is a little different. While I do these two questions to the dream (hence why it's in Sorphia and with two people Demetri's been very involved within his life) there is another bit to it that isn't related to the dream for Demetri and more for the reader.
After all, unlike flashbacks, dreams are made upon events not real or happened. They can replicate them, yes, but for the most part, they're for that moment in time and boundless in what they can do. This means I can do all kinds of writing tricks for them, be it foreshadowing, character reflection, worldbuilding, etc.
My views on dream sequences and flashbacks have made me question if putting them in is a good idea for [X] scenario or to explain this information, but I do find that they aren't inherently lazy craft. Sure, they can seem info-dumpy or a necessary bit to explain something of the plot in order to get important information to the reader and that can come off as cheap or passing by, but the two are honestly pretty moldable and aren't as limited as they may seem. Especially dreams, since dreams are all about whatever our mind thinks is funny to fill our head with as we sleep and all, aheh.
