So, knowing that I had three weeks at home, I ordered a new a new monitor to make better use of the new GPU and a new computer chair. The monitor arrived on Monday 23 and has been pretty awesome, the chair arrived yesterday, Monday 30. For an expensive chair it's pretty meh, but it's my own fault, it's an "Aerocool" and my subconscious was saying "No, you should buy a Vertagear". My subconscious was right, I saw a Vertagear and it had the seat-tilt I wanted, unfortunately the Aerocool does not and may be lower than my old chair to boot :(. It works for a 700mm high computer table but the desk I bought months ago is 850mm high.
My solution for the height problem is old bed pillows, because I need the height, particularly to get my arms above the desk. I may need to buy a new additional pillow (feather) because the old pillows (foam bits) feel a little hard.