Your kill switch has nothing to do with power loss from the battery unless you shut the bike down with it and forget to turn the key off. They stress using the kill switch in classes to get you used to it so that it is second nature in case of an emergency. I rode for about 20 years before I ever saw a bike with a kill switch.
The best practice in my opinion is to shut the bike off with the key so you don't come out from a stop and find the battery dead. Also less chance of forgetting the key and offering someone a test ride.
As for the trickle charger, if your battery was dead or allmost dead it will take at least 24 hours for a full charge. When the green LED comes on the battery is charged. for storage you should be using a charger/maintainer.

 

I bought a battery tender, and a cover from Walmart. I plug the tender in when ever it's sitting.

 

I also have a Walmart battery tender. Works great.
I run my tender on a timer....12 on - 12 off... doesn't boil it down as fast.
Battery tenders will help extend the life of your battery so it's a cheap investment.