I think your starting list is a very good one, and you've gotten some thoughtful input (no pun) from others as well. Much is going to depend on synergy with the rest of your system. I was trying to get the VAC Sig IIa for a listen in my system recently, and I know the version with the phono stage is highly regarded. Ditto on the Doshi.
I ran a Steelhead for a number of years, using NOS tubes, but found that it sounded best with an additional line stage in the system, not 'straight in.' It seemed to gain more weight and palpability with the additional component (at the time, a Lamm L2, which is, ironically a solid state audio path but tube driven power supply).
I may be wrong here, but it seems like most Shindo preamp owners also opt for standalone SUTs to optimize their set-up, so that may add an additional expense.
Obviously, if you can a chance to beg, borrow or 'steal' (proverbially speaking) these to try first, you are better off in the long run. Not easy, though.
Given the price point you are considering, you should be able to get great sonics. But, having just gone through a few months of experimentation with different line stages and phono stages (as separates), you will be surprised- I was- by the profound difference in your system these changes can make, even among otherwise highly regarded units. Thus, my emphasis on home trial if at all possible.
