I doubt you will find the steel bike more comfortable than your Roubaix, which has one of the smoothest rides of any bike out there. If the idea is to get the bars up even further relative to the saddle, you might try doing that on the Roubaix (different stem, steering tube extender, etc) to see if that's your issue before investing in a new bike.

Most folks that buy Rivendell do so for the panache, and also because they build great bikes. But bear in mind that they are essentially an assembler. They have frames built to their spec's, select the components, and put it all together. They buy at least some of their frames from Waterford, and you can buy the exact same frame, direct from Waterford, and save a lot of cash. Waterford has a lot of expertise to help you get the geometry right, plus the engineers to ensure no issues with the frame. Waterford has a less upscale division (Gunnar) that gets you a lot of the same benefits at an even further reduced cost. I own a custom Gunnar Sport. It's a fine bike, but I do most of my riding on my carbon Madone.