A more general rule for bigger monks is:
For each size step above Medium size, apply the following rules one time:
1d6 -> 1d8
1d8 -> 1d10
1d10 -> 1d12
1d12 -> 2d8
1d20 -> 2d10
So a Large monk starts with 1d8 damage, finishing at 2d10 damage, while a Huge monk starts at 1d10, finishing at 2d12.
40ft. base speed advances exactly as 30ft. base speed, i.e. 40ft level 1-2, 50ft. level 3-5.