Hi Scott,
Yeah, that's a great job huh ? Amazing. That's a good plan to do the old Airfix Bismarck first. White Ensign Models has a PE set for that Bismarck as well: WEM 1/600 "Ultimate" Kriegsmarine Set 1 - The Battleships
That set will outfit the Airfix Bismarck, giving you some practice on the PE as well. I built the Tamiya Bismarck in my early 20's some 25 years ago. I picked up another Tamiya Bismarck kit to some day do an "Uber" Bismarck like Ed's. My first Bismarck came out alright for it's day, but with today's PE and aftermarket stuff, my next Bismarck should make my first one look like a toy boat. I even wrote to Ed asking him how he did it and where he got the wood. He was good enough to respond telling me all but the largest molded on deck features need to be cut off and reapplied after the deck is planked. That may be a little hairy, but do-able. If you want the web site for the deck lumber, let me know and I'll post it. Also, if you really want to get nuts with this kit, you should get the brass barrel set from Steve Nuttal.
Don't worry about taking on more than you can chew. You'll get a better idea of your limits when you do the Airfix Bismarck, and then just work within those guidlines for the Tamiya Bismarck. The Tamiya Bismarck is a great kit and goes together real well. You'll be more than satisfied.
Ted