Can I ask God to let me live my own special adventure in Paradise, to roam in my own imaginary world, and see strange and wondrous places, phenomena, and creatures, and gain friends in this world, with the ability to leave it and return to Paradise whenever I wish?

In Paradise, there is everything that the soul of the believer desires and the eye delights in, as Allah Almighty says: "And for you therein is what your souls desire, and for you therein is what you request [or call for]," and His saying: "And therein is whatever souls desire and [wherein] eyes find delight. And you will abide therein eternally." So, a Muslim should strive in righteous deeds to attain this bliss.