Importance of the Preamp in a system

I currently own a Sim Audio W3 and had been pairing it with the Yamaha WXC-50 as the pre/streamer. All was fine until I got curious about tubes and picked up a Willsenton R8 tubed integrated. I was shocked at how different they sounded and how much more realistic and lifelike the tubes were to solid state. Everything seems a bit meatier with more separation between instruments, vocals, etc.with the tubes. It sounds more like a live performance then a recording. I pretty much stopped using the W3 and have considered selling it, but curiosity struck again and I did a little experiment using the Yamaha as the preamp to feed the tube section of the R8. The Yamaha has a switch that allows you to use it as a digital preamp with volume control or as a "player" with a fixed level output, bypassing the preamp section entirely. The R8 also has a preamp input which bypasses the pre section allowing it to be used as a tube amp. In this configuration the R8 lost a lot of the sparkle and realism that I loved about the tubes. It was much more dramatic then I expected, and easily ID’d as worse in a blind comparison. I was under the impression that a digital preamp should still sound great and possibly even improve on some areas by eliminating some of the characteristic flaws tubes have like microphoney. Actually I was under the impression that the preamp did very little to the system aside from make it louder or softer.

So this experiment really changed my opinion on the role of the preamp. I realize they can impact the structure and presentation of the sound and in a potentially significant way. So my question is this- do I simplify my life, get rid of the W3 and continue happily with the R8, or should I get a new preamp to better match the W3 and really unlock it’s potential? I’m wondering if I’ve even heard the true nature of the W3 at this point since the WXC’s pre section seems to be pretty bad. If I keep the W3, the two pre’s I’d consider are the SimAudio P3 (solid state) or the Freya+ which is a tube pre and uses the same style 6SN7 tubes that I seem to love in the Willsenton. Would that get the sparkle/realism back? Either would be under $1k, with the Sim a little cheaper then the Freya since buying used.