I'm just worried that since it takes its only rated to about 500 charge cycles (don't quote me) that charging daily will shorten the battery's life. I a daily charge average amongst most?
Do you think it is good practice to drain it all the way to zero every time before recharging or is charging nightly regardless its current charge safe to do?
Four words
Charge
Every
Night
Regardless
I plug mine in every night. Have done so since the original iPad.
You will get different points of view on whether or not you should let the battery drain to 0 once in a while. Personally I will let it drain to 0 around once a month in order to calibrate the battery. 95% of the time I will just charge it every night once I am done using it.
This does not calibrate the battery, it calibrates the percent charged display. It's actually harder on the battery than constantly topping it up and if done often will shorten the battery life. This "shock" to the battery stresses it more than topping up often from a partial charge.
That's what I do, I'd rather have more than enough power instead of not enough.
You bought it to use it. Charge it when it needs it.