From a drumming standpoint, it's inaccurate to differentiate between easy versus intricate Zeppelin tracks. Doing so confuses the concept of a beat with that of a groove. A beat is a mere numerical suggestion, a series of notes governed by a time signature and organized in measures. Any decent drummer can play a beat with proficiency. A groove, on the other hand, is a unique crafting and execution of a beat, shaped by each drummer's singular persona. No one, and I do mean no one, can replicate, in exquisite detail, the mysterious elements of Bonham's grooves, no matter how simple his beats may be. Abandon the pursuit before you disappoint yourself. Zeppelin songs are to be admired, not covered. I've never heard a good Zeppelin cover in my life.