I have been meaning to post as well.
I started off my home flight sim cockpit building many years ago)with an ABC (My Modified ABC Cockpit - SimHQ Forums - this isn’t mine but it is a good example of the plywood 3D puzzle construction used) pit. It was a good start and lasted a few years but had a couple of serious design flaws: 1. I looked like crap and was not helping me in my quests with the ladies; 2. The joystick and throttle positions either interfered with the keyboard or had poor ergonomics that would result in wrist cramps after any significant play.
That lead me to my Mk.II pit where I replaced the chair portion of the ABC with a modified desk chair - keeping the monitor/keyboard table of the ABC. The Mk.II was designed and built around 2005 using a surplus office chair from the office. I added a wooden frame to the bottom after removing the stock (connected to the base and the wheels) and added arms to hold the joystick and throttle at a somewhat ergonomic space. It worked well (and mas much more comfortable than the previous Mk but still was marginal on the presentable-furniture spectrum.
Here is the only picture I have of the Mk.II. At some point I had ditched the plywood parts for some … creative table making 
https://goo.gl/photos/YUHQJ4KU3oCJoQ6x5
I have stuck with this design through the years and iterated as new surplus office chairs became available.
Here is the Mk.III under construction:
https://goo.gl/photos/BkEHfPhpA11BnWwT7
Followed by the Mk.IV which used monitor arms off of the compaion desk. This was also the phase where I was using Helios and a central touch screen on the A-10C. This picture was taken some time after the Mk.IV was already in ‘service’ and I had upgraded to the Warthog.
https://goo.gl/photos/QsPQXQWT81tcgY2h6
Then we get to the current model: the Mk.V. This is the model I am most happy with. All of the other models allowed me to explore and expand my knowledge of building things from wood. With the Mk.V I decided to spend a little bit of money to make something that was much closer to real furniture that something that appeared slapped together from what might have been lying around 
If you don’t mind, I am going to put it together here has best I can from the pictures I have. I am proud of this one.
It starts with the chair from a 2010 VW Golf from a salvage yard - one that does not have any side curtain air bags.
https://goo.gl/photos/QNJfvPn5MLVyiXXe6
Strip out the bits underneath and add a frame to attach the follow-on bits to.
https://goo.gl/photos/tgu4163mTqXqbRP98
Stain it so that it will eventually look good.
https://goo.gl/photos/MB7PqSrRbS5yJp2G9
Build the arm base, both of them.
https://goo.gl/photos/mxtx7eqoni5pwFFg8
Add the modular top to each arm.
https://goo.gl/photos/HaRnL36wEmt7xUKW6
And attach them to the seat.
https://goo.gl/photos/n4gcXU4AarG1nbKj7
Take a break and spend a 6-8 months trying to decide how the rest should go. Then start with a base.
Figure out how the top is going to go on; those square bits match up to the two ‘posts’ that sit above the surface of the table for the monitor arms and the blank bit around the trim is where a small shelf goes and allows the MFDs to have a home.
Then we attach the top.
And add the hardware to get the final product.
I am very happy with how everything turned out. The CHProducts MFD panel from that first picture has a home where the tablet sits in the last picture. The keyboard is sitting on a modified monitor arm that sits under the desk tabletop, allowing the keyboard to ‘telescope’ out or be tucked away underneath. The PC sits behind the monitors between the two monitor arm poles and he throttle and stick sit down in their little recessed platforms. The MFD bases slide in on the top of that little shelf unit. Everything has a home 
I think that might be the closest I can make it to the realm of full-on acceptable furniture. I have a lot of pictures of chair and desk, so if anyone has any questions about any part of the design or build I can probably illustrate it. I have ‘plans’ but they follow no standard 
The only design drawbacks that I have at the moment concern adding additional pieces. If I want to add anything, I need to re-built parts but luckily I have built the set to be modifyable. I would like to have a place to put a helicopter collective but that would be the most challenging part of any future modification.
Well, that and Thrustmaster or some third party coming out with a new stick/throttle combination.