Got BAT VK-60 ...now what?

Recently, I bought a BAT VK-60 - which in fact, didn't even arrive, yet - but I'm already eager to persue further upgrades.
My current system is : AP Virgo, Sim Audio Moon I-5 integrated, Rega Planet CDP, Audio Analysis Silver Oval 9 speaker cable, HT ProSil mkII ICs.
Temporarily, I plan to run the I-5 as pre amp, but eventually I'd like to replace it with a 'real' pre amp. An obvious choice would be a BAT pre and I did already some research here on A'gon and Audio Asylum, but quite frankly this left me a bit confused. There are tons of different models (VK3i, VK30, VK30SE, VK5i, VK50, VK50SE...) and I simply wondered which one would be the best choice. Unfortunately, I can't afford the VK50SE (I want to stay in the 2000$ range). So, which one is better for instance? The VK30SE or the VK5i? How do they all compare to each other? I'm also entertaining the idea of getting a Pass Aleph P (incidentially, one just popped up for sale). Would this be a good match with the VK-60?
Any other suggestions would be welcome, too. Oh, and what kind of power conditioner or at least surge protector works well the VK-60 (I know BAT recommends plugging it straight into the wall)?
Thanks