It's kinda funny...I've never considered a blend that comes broken or rubbed out to be a flake. I mean, I know they are...or rather were...but unless I have the option of either leaving it whole to roll, or to transmogrify it to another of its potential forms...I don't think of it as a flake. Just me. Never mind. Forget I mentioned it.
Re: the pipe...two...almost any Prince (since it's the shape, not the brand that makes it such a fine flake cooker). Then I like a medium Canadian almost as much. It just seems that those two shapes (much has been written about the Prince bowl shape), unless there is some mechanical issue with the pipe or its airflow, will do really well with a quality flake regardless of the wood, brand, etc.
Re: which flake...two...Stonehaven for its dark treacley sweetness...and Gawith & Hogwarts Dark Flake for its unabashed strength and unapologetic character.
(What am I smoking the most of right now? Sherlock Holmes Pipe Club's VRBlend. Good ol' Russ Oulette. What a guy! He's got 3 - 4 of his in my top ten list. A singular achievement. He must feel quite special to be so honored. lol That VR is really something. Between it and Stogie and Virginia Squire, ol' Russ has sucked up a pretty fair percentage of my weed fund. Good for him!