With the Kick, I'm only concerned with sound. I don't really worry about bleed when placing the mic. If it's inside the shell, bleed is unlikely. If I end up with the mic on the outside, I'll often drape a heavy blanket over it and hope for the best.
The snare, on the other hand, is a different story. I try first to reduce bleed based on placement of the pieces of the kit. The hi-hat is my main concern here. Also, how hard the drummer hits his cymbals is a huge concern. Next, would come mic placement. But, even then, sound is more important than bleed.
After all of that is taken care of, if there is still a problem, I will use a gate. But, without full attenuation. I would NEVER gate before the sound hits tape/hard drive. Also, look for a gate that has some kind of look-ahead feature to avoid chopping off your drums' attack.