<nerd>Canonically, the deflector dish is on the front of the spacecraft so that at warp speeds it can deflect space dust out of its way.</nerd>

If modern-day humans are able to predict its orbit, the Enterprise... any of them... can handle it. As befits a science fiction ship.

I believe that was addressed in canon, the Vulcan scene in ST2009 notwithstanding. However, in Into Darkness, I recall an aside that the Enterprise would incinerate on reentry unless shields were restored, indicating utility beyond weaponry (that they did not, even though the pivotal moment was long after they were in blue sky, was a bit confusing).

You and jerf both have me hopelessly outnerded. I bow to your superior knowledge.