For the average person Tube Amps are impractical. They tend to be expensive and low powered relative to the price.
I also dispute the "...forward solid-state amplifier...". Solid State amplifiers can have any sound the designer desires. They can be warm, neutral, or bright. But generally, all amps are made work with all speakers. Do keep in mind that a very vast majority of amps sold are solid-state by a very wide majority.
Yamaha, at least in Stereo, are not noted for being bright amps.
And sometimes the bargain simply rules the day. For £199 I can't think of anything even remotely close to the Yamaha AS501 for a blend of Power, general Quality, and Features.
If about £200 is your desired budget, I can't see anything else for that money. However if you can go to a higher budget. Then perhaps one of the Network Receivers (RN500 or RN602).
As an example, the Marantz PM6005 might be a bit better sounding amp, but it is 45w/ch though it does have a DAC with Optical and Coaxial, and it carries a price tag of £299 which represents a savings of £80 over the Retail Price.
However, for £10 more you can get the Yamaha RN500 Network Receiver with 80w/ch, DAC, and Network Streaming.
At some point you have to find your personal sweet spot where Price, Power, Quality, and Features merge to give you exactly the blend you want.
But at £199, there is really nothing the equal of the Yamaha AS501 ... in my opinion.
Steve/bluewizard