At the very outset I offer my apologies for wading into this rather heated discussion. This is a shot I took with the 6D. Please let me know how a Nikon camera would have helped with this.
I'm just a hobbyist and humble student of photography ... HELP!
I like your shot and glad you got a 6D instead of going the cheap route with a 5d2.
the 6d has improved significantly in areas where some of us cursed the 5d2 as PoS.
the shot, even if it was level in reality (likely not?) would likely appear a little better with some rotation applied to provide a more natural symmetry and sense of vertical balance.
tho many of us are horizonally-challenged despite the best efforts of built in artificial horizons. I need Pentax's built in auto-level sensor rotation.