Margot, that is an ambitious small system; obviously, you are looking for quality and aesthetics. You are aware, I presume, of the low frequency penalty? Smallish systems will not produce much of the frequency range responsible for tactile sensation and a deeper recreation of the sound stage. That is not a judgment of Audio Note, but it is a factor involved in all smaller speaker systems, even if placed into a corner. However, you are discussing a smaller room that is closer to square, so the size speaker is not far off.
As to tubes and room temperature, it is a great question and pertinent. If the room is well insulated, yes, the tubes can be a problem. I do not know directly about AN gear, but it does not take much to bring a smaller room’s temperature up several degrees. Some people have alternative amplification to switch between heating and cooling seasons. I caught that you had another thread wherein you asked about low power amps and heat. Seems that may be a concern, so I would give it plenty of thought regarding tubes in the smaller room.
Finally, another aspect of selection of speakers that perhaps you are already acquainted, their genre. There are different philosophies of cabinet construction and design of speakers. The AN family is part of a genre of speakers that have less cabinet bracing and cabinet deadening properties, but instead try to tune the cabinet to make its contribution to the sound fitting.
Other speakers are opposite, where the cabinet is quite dense and the goal is to reduce as much as possible the cabinet’s contribution. Dipoles or hybrid dipoles, etc. are another option, i.e. Eminent Technology LFT-16, which is somewhat shallower in the bass but would present quite differently. You also would want very different amplification.
I discuss in my book The Audiophile Laws the most popular genres of speakers and their characteristics. Selection of the genre of speaker is as critical to long term satisfaction as the quality.
Disclosure: I reviewed and owned the Eminent Technology LFT-8A and LFT-8B versions. Review is at Dagogo.com