Climbing the Preamp ladder

Bat vk-3, Manley Shrimp, and am currently using a Bat vk3-ix. you see I like tubes. what is a good step up? not just different. I use a Rogue stereo 90 tube amp with Aerial 8 speakers. I have a musical fidelity m1 transport and a wadia 121 DAC. I would like to stay under $2500.

thanks for everything in advance.