Yes, I follow your series of vids quiet dillegently. I'm starting off in 1930 as I've refreshed everything before run the V2 mod.
Cetianly I've found with the light cruiser design that 35kts isnt possible so I've had to scale that back to 30. - but that is using a 7" 50 cal main battery, rather than the more tradition 6". The heavy cruiser hull has an optimal speed of 33.1 kts, but that is entirely aspirational know. To get close the ship needs forced boilers and a minium of two funnels which adds to the size and overall weight.
I'll have a look a redesiging using your suggestions