Hi Cassius
I am 3 inches shorter than you and 16kg lighter.
My fist frame used similar size tubing to your planned build and slightly thicker gauge (8/5/8 ) The exception being that I used a smaller head tube for a 1" steerer. Reynolds 631 tubes with 725 stays.
I have been riding this bike for 15 years and have been very pleased with it, it is very comfy to ride and is excellent for long distances or commuting. However, load it up or ride it hard and it does start to feel a little flexy.
I recently built my second frame from Columbus Life double oversize tubing 8/5/8 DT 7/5/7TT 8/6ST 1.1HT and whilst being a little harsher, is much better for riding hard.
The recent frame weighed 1992g the first frame 1996g - go figure that one out! This is probably because the Columbus life stays are much lighter than the Reynolds ones.
With your added size and weight you might find your proposed build a little on the light side - but I am no expert, wait and see what they suggest :-)
Good luck with your project and enjoy it.
Which side of the pond are you? Just notice you are using metric.