I would be helpful to know how close you now come to running out of clean power. With tube amps, you don't get the shrill, harsh output from the tweeter that you get when solid state is running out of gas--you tend to first experience compression (you turn up the volume but it doesn't get much louder), followed by a muddled sound lacking in clarity and imaging starts to break down. If you hear that at very high volume levels, you have to decide how important reaching such levels really is to your overall listening enjoyment (I don't like to listen at high levels, so I don't give high volume capability much priority, but, you may differ in your needs). You could also get a cheap meter that measures how many watts are being delivered to your speakers. At a fairly high volume level, you generally want to stay below 1/4 of rated power of the amp, except for the very occasional peaks.
Most people grossly over estimate how much power they really need and end up chasing the wrong thing in their quest for better sound. Nelson Pass created a company dedicated to making really good solid state amps optimized for delivering great sound at lower power levels--the company name "First Watt" reflects its philosophy. As that company put it--"Who cares what an amp sounds like at 500 watts if it sounds like crap at one watt?" I've heard a couple of these First Watt amps and they are among the best solid state amps I've heard. I think the same can be said of tube amps. Most of the very best I've heard were low powered. Unfortunately, low-powered tube means REALLY low power. I own three tube amps, and the one with the highest rated power is the Audio Note Kageki at, I believe 6.5 watts per channel. My current favorite amp that I own is a 5.5 watt per channel pushpull 349 amp. My all time favorite amp is a custom built OTL amp that I think is rated at something like 20 watts (maybe more) that a friend owns.