Grist for the mill: That's a very large room with dimensions requiring serious consideration (i.e. ceiling height; loft; etc.), not to mention speaker placement. Most high-end audio shops are likely not going to have audition rooms remotely similar should you decide to venture out for some critical listening time (i.e. shopping). That being said, considering the amount of dough you are considering spending, what's a little travel time? One way or the other, I would recommend you do business with someone who has a generous return policy (i.e. as little hassle with returns, return shipping and no or low restocking fee(s)) in the event you bring something home that just doesn't quite cut the mustard in your room, if you know what I mean.
I spent many, many hours of critical listening time the last time I went hunting for an integrated amp. I very much enjoyed my time with a Luxman, as well as a McIntosh, Musical Fidelity and Simaudio Moon. Back in the early 70s, I loved the time I spent with a Phase Linear amp but this was before they became jokingly referred to as "Flame Linear" due to their propensity to overheat and, some say, sometimes catch fire. I've also spent time with Anthem amps and liked them very much, as well. I've owned a Yamaha 80 watter with "Pure Direct" circuitry, but this would obviously be much too underpowered for your room. Adcom impressed me, back in the 80s, as well. More recently, I found a few Rotel and Denon integrateds interesting but not in the same class as and others I've mentioned here. I've read great reviews of some of the products others have mentioned in this thread but haven't heard them. If you can, you might want to have a listen to a McIntosh MA 7200 with the DA2 DAC option. Just sayin'. Extra (clean) power isn't only about "loud" but also about headroom, the ability to appropriately handle tone bursts in music and a few other considerations.
So, all this boils down to another opinion of what MY ears and some other ears like, which very well may not be what YOUR ears like. In your position, I wouldn't let travel time concerns dissuade me from scheduling some critical listening sessions. Have fun with it and, as always, trust YOUR ears!