Terribly unrealistic. Archery is going to be almost all of your Weapon proficiency points, or you aren't going to hit the broadside of a barn. Meanwhile, you can get away with 50 to 75 melee proficiency in your melee weapon of choice. Melee can almost never be "spammed" to death with even 1 wpf point, it comes down to footwork [Matching enemies' footwork patterns/not getting circled/stepping into your swings] and attack as soon as you hear the sound of you blocking. Best of luck to your archer/2h hybrid ^_^.
Even now at level six with a short bow and basic arrows, I find I'm able to hit most anything at a range of about fifty yards or less. As I said before, I was wanting my focus to be on the melee, not spamming in any means but simply being a feasible opponent to others, standing a chance in battle, and racking up enough kills that I'm not entirely useless.
I've come to understand what you mean about footwork, and I realize it's going to be a lot of work learning how to handle it but this is by no measure an impossibility for me.
While I realize I've got a lot to learn still, I DO stand by my belief that this is at least a viable build to attempt. I simply wanted a generalized idea on where to lead it. I don't yet understand all of the intricacies that go along with building any form of character in this game, let alone one along the lines of a more complicated "hybrid."