In this situation, I would rather have hypersecretion, this means that there is an excess of adrenaline produced. Due to the fact that adrenaline triggers the body's fight-or-flight response you will be ready flee when you see the rattlesnake. If you have hyposecretion, there will be less adrenaline, meaning you may react slower and not be as prepared, possibly resulting in you getting bit.
Honestly, hyposecretion is the better choice because too much adrenaline can damage your blood vessels and increase blood pressure, which we all know isn't good. But too little adrenaline will result in you not properly handling the situation. Rattlesnake bites are rarely fatal, so it can be treated, but with too much afrenaline can also result in heart attack and stroke.
