I like your project too
(just read the thread on the external gate mod)
It is the reason why I never went to do it after trying so many vendors twins run in parallel ........... the boost curve and matching torque is always poor.
By example my 82mm compressor 1400bhp capable turbo spools faster and earlier than your twins but it is not as cool LOL.......... I think that is what TTT is getting at with his single comments.
The BNR's I tested showed the same power band as you have found and its roughly line ball with a ball bearing GT28 cartridges run in the twins frame in parallel. Just a poor set up really but if you want to do it then its your car
and everyone is different.
Will be good if you can test it and we can see how fast it is
90kmh to 140kmh in 3rd
100kmh to 200kmh (3rd to 4th) and lets see some numbers