...eventually, some one will think the X-frame is a bit under designed...

Another car analogy for you:

Compare a 1955 Ford to a 2012 Ford.

As to that point, how many 1955 designs of ANYTHING are still for sale by the original designer, still kicking, still doing it's job better than most? A few, but not many, and whatever they are, they are classics and timeless in the best of terms.

Know what you need, get what you need. That's it right there. If I wanted 0-60 in 5 sec, airbags, and traction control, I would not pick a 1955 car!