I was going to suggest dropping the treble. Almost such that it points at the mid range control. The treble does not really add much but when dropped it cures the ice pick of the Lo mode. Bass, almost the same thing, point it at mid range control (or almost at it). Use the Mid to dial in your tone as it serves as mid and treble and alters the gain characteristic. The gain setting also seems to add presence to the mix. As for power tubes, that will make a huge difference in you overall sound. I prefer the SED EL34 in this amp but they are very hard to come by and if you find some they will be expensive. I found the Mesa (which are same as EH EL34) to be very bright but you can dial in a decent sound with them. Tung Sol EL34B will have a bit more bottom end and will be much louder. Mullard EL34 are very potent in the mids and top end and seem difficult to control the gain with the Hi/Lo settings. Right now I am running the Mesa EL34 and so far I am enjoying the experience. What I have not tried in this amp: 6CA7's. That would prove to be interesting when I get around to finding a good set. For a while, I was using SED 6L6GC. That is very impressive tonal bliss. I can get some similar tones from the RA100 with 6L6 as I get with the Roadster or Mark V. However, the overall tone of the RA100 is more midrange, it still sounds like I am running EL34's but with more depth on the floor. I have tried the Mesa 6L6GC-str440 and was not impressed with those tubes in the RA100. Those had that blanket over the cab tone. They are perfect for the Roadster, okay for the Mark V. I actually prefer the EL34 type tubes in the RA100. Have you tried using the clean channel as a moderate gain channel. Boost the gain control, drop the bass a bit and push up the treble. It may also help to use the multi-soak set to -4dB. If you want vintage tone that is crunchy you can get that on the clean channel. Note: does not work well with 6L6 power tubes but it is not all that bad.
I also am using a Mesa OS Recto slant 412 cab loaded with V30 and could not be happier. For a short time I did have an old Recto cab loaded with EVM12L BL but that was way too dark, especially with the clean channel. I did restore the old 412 cab back to original, so what is more exciting is running a full stack equivalent. There will be some roll off of the high frequencies and upper harmonics that cause the ice pick effect.
Very interesting. I kind of would like to experiment with power tubes, but if I pay for the really good ones, I will just eat them up anyway. I drive the heck out of them on this amp.
For tone controls, I agree, but I prefer the Treble at 10:30. I like to have a bit of top end. Though I may try dropping the treble and bringing up the mids a bit. If that gives me a bit more mid harmonic complexity and fills in the top, I'm sure I'll dig it.