Re: holes in the kick drum....
I have a 24" ludwig bass drum. I have a solid reso head with a felt strip. No other muffling. I like how it sounds.
Next time you play a show, ask the soundman to mic the batter side. That's what Bonham did, along with micing the reso head. But if you have just one mic, try putting it on the batter - will pick up more attack.