R2 can be 1/8W.
R3 can be 1/4W.
R5 can be 1W.
R6/R7 can be 15W. I would change those to 47 ohm 10W.
R8/R9 can be 1/2W
I didn't notice how big R10 is. You don't really need the plate choke when you could already have such a giant dropping resistor, but having the plate choke would allow you to put in some over voltage protection for the 12GN7. When you turn the amp on, you will have 1300V appearing at the 9 pin socket, which is a recipe for disaster. You could put a string of Zener diodes in from the junction of the plate choke and the 68K resistor to ground to pull that down to 500V DC until the 12GN7 conducts and pulls it down further. This would give you a lot of safety benefit and would also protect your coupling cap, which will fail in this design if it's only rated for 1kV.
Is C4 the cap after the 68K resistor? Without Zener protection, this should be rated for 1.5kV. With Zener protection you could use a 500V rated cap (use Zeners to pull that node down below 500V at startup).