Generally, I try to reciprocate eye contact depending on the person I'm speaking to. When looking at a person, I try to shift my attention every couple seconds between one eye, forehead, etc. If it's a girl I fancy, I try to look into her eyes a little longer (in hopes that my green assets suck her in
)
That said, I would imagine that people prefer too little eye contact to too much (the latter usually creeps people out, especially me
). There are also certain situations where I make the bare minimum amount, such as driving.
I wouldn't sweat about this too much, the fact that you're aware of this stuff and trying to address it will do a lot of the heavy lifting for you 
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"The superior man is the providence of the inferior. He is eyes for the blind, strength for the weak, and a shield for the defenseless. He stands erect by bending above the fallen. He rises by lifting others."
- Robert G. Ingersoll