Yes I am thinking the AVA non-tube "SLR" all solid state version to pair up with the Aleph. An all class A pre and power is appealing in general to me.I previously owned the FET Valve CFR. While it's a nice preamp in many respects and unmatched in terms of price/features, I prefer the Schiit Freya Plus for absolute sound quality. The Quicksilver headphone amp performs even better than the Schiit.
I had entertained the FET Valve but at an extra $800 over the SLR Im not sure I want to go there. A used FET Valve or maybe a used Rogue RP-1 then tubes might enter the consideration with a couple more options.
That said, of the initial two on your list, definitely go AVA. You'd probably have to wait no more than two weeks to receive the preamp and Frank is a saint in treatment of his customers compared to some other(s).
Schiit isn't my favorite regarding customer service but they're certainly not terrible. For performance/dollar, the Freya+ is exceptional. Only caveat is if your system needs a balance control.