Are you sure you're not just drawing false conclusions from some other game? Personally I would think that if I was "good with a bow" my target would almost be dead by the time it gets close. So the Melee part would only be a "finisher".
But you are right about one thing... You only get "really good" with a weapon by using it. So to be really good with Melee weapons you would have to "put your Bow away" and use something else. The Flip side is that if you insist on Only using a Bow. By the time you hit 50. You're comparative skill, with any other weapon, won't be very good.
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I think I understand part of how you feel. One of my planned characters will be a Bosmer Nightblade. And I wanted his Primary Weapon to be the Bow, for RP reasons. But I suspect its going to take some adjustment on my part to develop my Dual Wield skill so I don't have to "kite". Despite the fact that the Nightblade skill lines do have a few skills that would very handy for Kiting. Still that's all down to personal preference.