Design feedback request - Dumble meets Champ

[ODSChamp]

Hoping to get some feedback on this schematic. This is my first attempt at an amp design, though really it's just an unholy union of a Fender Vibro Champ and a Dumble clean channel. Can anyone see any issues with this design? I'm mostly concerned about:
- the 220k resistor to ground before the 6V6, will the preamp gain be significantly different (I'd imagine lower) from the original Champ design to warrant a different level of resistance here so the 6V6 gets an appropriate signal level/impedance? Is there a way to determine this or is it just "try a few values and see what works best?"
- is the 50k RA (intensity) pot & 47k resistor in the tremolo circuit going to work? The original champ design calls for 68k and 25k RA, but I couldn't find that value. My thinking was that if anything it might deliver higher voltage to the cathode of the second gain stage, which may result in deeper tremolo (a good thing in my opinion). Are there any other issues?
- are there any issues with the different bias for the second gain stage with regard to the tremolo voltage coming in at the cathode? The Dumble design has a very different bias (and, I assume, gain level, though I'm not versed in this stuff enough to be confident trying to calculate it). How will this different bias affect the tremolo wiggle bias coming into this gain stage? I'm willing to build the amp and find out the hard way, but I'd like to be somewhat prepared and know what to do if it doesn't work
- same question but with regard to the negative feedback. It also comes in at the cathode of the second triode. With the different (Dumble) bias, will this affect the level of negative feedback that will work? If this and the tremolo aren't working at all, I suppose I can just bias that stage like the original Champ...
- I'm fairly confident the transformers and 450V filter caps will be able to handle inrush current without a tube rectifier, but just to be safe I'll be putting an NTC thermister on the 120V side. Anyone see a problem with this?

Are there any issues I'm missing? I appreciate any feedback you guys can give! Thanks.

[Stevem]

This characteristic chart tells you how much audio drive signal you need.

You can even measure it with a voltmeter set for ac volts.

[didit]

Hello —

A thread of good semi-related reading ::

https://ampgarage.com/forum/viewtopic.php?f=4&t=37090

..