Paradoxes of Relativity

The didactic Einstein ruined many a physicist’s life with one definitive claim: the speed of light is absolute, and time, length, and mass change depending on the frame of reference.  Like a massive, perpetual migraine, physicists mulled over this paradoxical statement and found the answers they came up with paradoxical within themselves.  I am no physicist, no, nothing more than a humble English major attempting to comprehend the grandeur that is physical science.  Perhaps my open mind and analytical way of thinking took the para-out-of-this-dox; I can see what Einstein’s saying quite clearly.  Explained simply, a person’s time, length, and mass changes due to their speed relative to other observers.
Let’s say there are two physicists of the same age.  One goes on a space trip at speeds near that of light, while another opts to stay on the safer terra firma.  The undaunted physicist’s biological clock slows down, and that means no wrinkle cream for him at 55!  He can come back to earth young as ever, and find his less adventurous comrade has switched from football to golf.  The situation can get sticky if one wonders, wouldn’t the biological clock speed up as the traveler returns to earth?  Wouldn’t the frame of reference cause the physicist in the ship to age faster if reversed?  There are many more questions, but the solid argument lies in concepts of time dilation, length contraction, etc., so why ask why, a future lawyer might conclude.
Speaking of length contraction, let’s say there is a parking pad 5 meters long.  A ultra-futuristic hovercraft, 10 meters long, is traveling fast enough near the speed of light, and since Einstein's special relativity requires the hovercraft’s length to shorten, let’s say that the speed of the craft is sufficient for the craft’s length to contract to 5 meters.  At an incredibly high speed, photographs the craft passing over the parking pad.  During a very brief time, the 10 meter hovercraft fits the parking pad below it exactly.
But then again, why ask why?  If the desired effects are achieved, gung ho into the future and the possibilities, I say!