Good idea to change these resistors to a higher value on Hiwatt?

[frank57]

Suggestion was made to up  r33 and r34 to 100k.
Good idea?

[FYL]

47K is on the low side, but should be OK with EL84s. You may try 100K.

[frank57]

What exactly is their function?
To protect the power tubes?
I don't notice much change in the bias  or anything like that.

[FYL]

Bias mixers and grid leak Rs. There's very little current across them, so their impact is small when it comes to bias voltage.