Fantasizing over Fantasies

My concept was Invincibility, while this in itself is a narrowed down version of a fantasy concept, I've come to a stalemate with it.  All of my art and sketches seem fantasy based beyond just the invincibility aspect.  I feel as though I should pursue pieces in that direction because that is what I am most motivated and inspired by.  I would define fantasy as:  Something not achievable at the current date.  An example would be drawing a world with hover cars;  Those don't exist and won't with the tech we have now, however it could most certainly be a reality in the distant future.  I believe I could also do work on invincibility because though it isn't achievable now, it could be in the future.  As to how that could happen will be left to the imagination and transferred to paper.   I also feel more inclined to doing fantasy work because there is a whole universe I could create pieces for, and I believe having many pieces that tie together some how is much butter than a lot of pieces that have no real connection.  I could for instance take a transformer and put it in the future disguised as a space ship.  The ability to tie in many different ideas that link to each other has always been something interesting to me because as the pieces develop, the ideas evolve and change with it.