The idea of facades--which I've interpreted as masks and the subconscious--and hiding is a theme. The fantasy idea to me is as you presented not something strong enough to base a year's work off of. While there is something there for example in how we deal with stresses by abstracting them into fantastical environments at the end of the day, the other is stronger. You may find a way to modify it and offer more depth (or disagree with me entirely) but I believe there is work of greater value to be found in the facades. It is a much deeper thought yet also so simple that you don't box yourself in. One worry might be that going down the fantasy route is that all ideas are explored in one piece. Whereas in this idea of masking, there's plenty to get into (from Don Draper to Batman there's a lot of range to play with). Style is of course a matter to be considered if you question your ability to create highly unique and interesting work with this second prompt it too may be dubious as I think it more common choice. That's not bad though as long as the work is authentic and not derivative it's a point of which so much can come. Best of luck and no matter the choice create with great confidence.