I'm a little taller than you at 6'3", had a couple of long blade bats but mostly used standard short handle (used other players' long handles and can't stand them). I grip the handle pretty much bang in the middle and never had a problem at all. Would maybe suggest your stance needs looking at? Longer bats can be useful in giving you a bit more reach to the ball, but if you're bending over uncomfortably and holding the bat in a way that's not comfortable, that to me says your stance isn't right and a 1" longer bat isn't gonna make much difference.
A picture would help, but do you tap your bat and then straighten into your stance, or is your bat on the floor as the bowler delivers? I assume the second, would an adjustment so the bat isn't touching the floor help? Can't be good if you're in an uncomfortable position as the ball is released, I'd suggest trying something more natural and not worrying about where your bat is.