Class D or Hybrid Amp for Fritz Rev 7 speakers

I am a long-time member but very seldom post. However, I value the expertise here as I have not bought a lot of audio equipment in my day. My goal in 2014 is to upgrade my power amp to hopefully get more detail, a better midrange, and better soundstage. After upgrading the amp, my plan is to upgrade the pre-amp in 2015.

I had some great recommendations on potential tube amps but when I started reading the manuals, I realized that I don’t have the rack space to suit a higher powered tube amp. It seems like there is a lot of discussion here on Class D so I thought I would ask for comments/help.

My current system consists of MacMini/Rega DAC/Acurus RL11 preamp/Acurus A250 power amp/Fritz Rev 7 speakers. The Rev 7s are 4 ohm, 89 db sensitivity. I plan to keep these for a long time so want an amp to match. The Acurus equipment was modded a couple years ago.

My budget is approximately $2K used or new. As of now, my plan is to try a hybrid tube amp (Rogue or Audio by Van Alstine) or Class D amp. If I don’t get one of the hybrids, I would be intrigued by Class D amps such as Channel Islands, W4S, and Bel Canto.

One criteria is that they would have to be compatible with a tube pre-amp as I wan tto try tubes somewhere in my system. In 2015, I plan to upgrade the pre-amp. I have not heard Class D or tubes extensively so I don’t have a strong inclination. However, it seems that I could put together a nice combination using a class D or hybrid with a tube preamp.

Given my budget and system, are there any obvious combinations that you would recommend? Thanks in advance for any comments.