Hah! Thanks Morticai, an interesting illustration. However, I understand the definition of complex and muddled, I just don't know in recipe design what makes the tipping point. I am really looking forward to the Grain book that will finish the Yeast, Hops, Water series - at least I hope that corrects the gaps in my understanding about this issue. In the mean time I ask questions here.
I think complexity comes when you combine subtle characteristics that, by themselves would not make much impact (soft melodic vocal music) and perhaps 1 bold structured characteristic that provides the platform for the rest. Often times people pick big bold flavours that they really like and decide that if they put those together it will be complex. That's when things get muddled.
Take farmhouse style brews. they tend to be very complex in flavour and the recipe itself can look very complex, 1 or even 2 or 3 raw adjuncts, some simple sugars, lots of hops early and late. Add it a very complex and lively yeast character and there is a lot going on.
But raw adjuncts tend to be pretty subtle in the final product, perhaps some mild phenolic spiceyness from rye, creaminess from oats, or tartness from wheat but never to the 'Whoa, Wheat!' level. I do about 24%-25%
I think with farmhouse style the backbone, the one bold, structural component is the yeast. It is spicey all by itself. if you are using a pure strain you get some spice, and fruit, and maybe a touch of tartness (the belle will give you some citric type tartness for sure). If you use a yeast blend like many farmhouse brewers the yeast complexity gets even greater with some brett in there lending farmyard funk.
I like light (10L) munich for adjusting color because it gives a subtle toasty bready sweet note but nothing over the top like a dark crystal. It supports the other players by giving the malt base some weight. i don't actually have a preference between pils and pale for the remainder of my grist although if you like a little perceived sweetness pils can provide that. I go with about 24-25% munich to about 36-37% other base.
the rest of the fermentables should be from simple sugars. I insist still on using something more interesting than table sugar even though I am not convinced it makes any significant difference. But when aiming for complexity sometimes things that are so subtle you aren't even sure you notice them make a big difference. (like when working with nutmeg always add a little cinnamon, you may not notice the cinnamon but it will help make the nutmeg pop) So I like honey, or raw sugar, rapidura, maple syrup (can emulate some wood character if you are rich enough to use a bunch), coconut sugar.
I have not found a huge need for spices yet. but I haven't experimented with them much either so I could well change my mind about that. They do tend to be easy to over do.