Barbequed Brisket, cooked over an all wood fire, is kind of the holy grail of barbecue. If it was easy, a lot more people would do it well. However, once you've done it successfully a few times, it comes down to choosing good meat to begin with, proper trimming (1/4" isn't all that easy until you learn how), fire management (which has a LOT to do with the pit), good meat and injecting, cooking to the right internal, and properly resting.
A lot of "all wood fire" is the pit. If you're trying to run an all wood fire in too small a pit, you're hosing yourself. Even if you keep even temps, one slightly funky piece of wood will wreck you. IMO, Barbecued Brisket cooks better at a higher temperature than pork. I usually cook at around 275 -- which is not an easy temp to hold in smaller pits. Much over 250 and a runaway fire is a real possibility.
That said, you can make brisket every bit as good in a small pit -- you just have to use a mostly charcoal fire. A little bit of hardwood chunk in the charcoal at the right time in the right way will put every bit as much smoke into the beef as an all wood fire in a big pit. I think the prep and management techniques aren't all that difficult as long as they're suited to the pit. Charcoal baskets are an enormous help in smaller offsets. The biggest obstacle to managing the fire in a small pit are novice pitmasters. They insist on doing it the most difficult, most wasteful, least reliable ways as though there were some virtue to them. One constant, they always have reasons.
Barbequed" Chicken, whether grilled or actually barbecued is mostly a matter of simple techniques. Admittedly it takes a rather large bag of tricks to cover all the various styles, but when it gets down to it the techniques are more numerous than difficult. One of the few constants is brining. Brine your chicken, dag-nab it! Interesting note: Chicken is generally best grilled over a low fire, and smoked over a hot one. Go figure.
Intewestingwy, wabbit can be cooked outdoors in many of the same dewicious ways. Or even fwied or a fwicasee if you have a pwopane burner. Heheheheheh.
Beef Wellington (Wehwington?) is a lot of prep; nothing really difficult about it. Unfortunately, a fillet of beef does not benefit from being cooked en croute. No way. No how. Admittedly some are better than others, but bottom line: Not so much difficult as impossible. The Duke of Wellington, at least the one who defeated Napoleon, did not eat it. That's a canard.
Speaking of canards, I used to make a PITA called Stuffed Duck Charles Vaucher, cribbed from Pellaprat's cookbook. Sort of a turducken on steroids with PMS, but lacking the sense of humor -- possessing instead a stick up the vent.
"Imagine if you will," removing the bones and the meat from a duck -- except the drumsticks, and wings -- without breaking the skin; make a rather complicated farce with the meat, some pork, truffles, olives and the rest of the usual over-priced French suspects; stuff, sew, and reshape; a fussy braise; chill and coat with aspic; blah blah blah. You get the picture.
The first time I did it was to challenge myself, and the second time to pefect it. Then I started bragging about it. Mistake number one. Then I put it on my catering menu, and kept it there when I moved down South. Mistakes number two and three. Then I served it at my self-catered wedding reception which included a number of clients as guests. Mistake number four. This was on the way to being my "signature" dish when I quit catering. In fact, the thought of getting one more request for "four of those duck things you do" was a big part of the reason I quit catering. Now that I think about it, I have no desire to make it again. None. D'rien. Don't even think about it. I can't hear you.
Chicken Marengo is otherwise pretty straightforward. but for the mushrooms. It's not the fluting that bothers me, it's the peeling. Something about peeling a mushroom just chaps my @ss. DW's worth it. The only other people on the planet I'd do it for are my kids.