For starters, personally, I would lose the McIntosh, because apparently from what I've learned on this site they have what we call a house sound, meaning that while it's extremely high fidelity it's different from all the rest. What I was told is to make sure it's your cup of tea because it'll be expensive to replace it if you don't.
Especially, as far as speakers go, but probably for all the other components as well, you'll get way more of a bang for your buck buying used gear, as in, on this site and I have no affiliation except for being a very satisfied user who's scored a few amazing deals on even more amazing equipment. And, dude, the biggest piece of advice I can give you, esp since you said your kind of (exceptionally) cool wife isn't gonna allow you to sink any more bucks into this little foray for a long time ... is to do it right the first time. It's called upgradeitis and it's expensive as hell. As long as you spend your money well I'm here to tell you it won't be a thing.
This forum is full of people chasing the dream. I had but a system years ago when I was married to the mother of my children and I was more careful about my choices when I decided to build another system just a few years ago.
It's terribly important to have a high degree of synergy b/w your different components. If you do this part well, I can pretty much assure you you'l never want to upgrade b/c when you have good synergy you won't need or want to change anything.
I'm going to personally recommend my speakers b/c from what you've described, what we call the WAF, which stands for wife approval factor is pretty important since you guys are doing this together and I'm sure you want to please her.
One of the reasons I could justify spending as much on my speakers as I did is because they're gorgeous. To prove my point above about used gear, I'm the third owner of my speakers. I bought them from an opera singer down in Houston TX. I'm not sure what he paid for them but the original owner paid $11,000. Frequently, there will be two or three pair listed on this very sight for $5000. I got them for a little over 3K and they're in awesome condition. Even if you get a pair for between five and seven grand, look how much you save buying used.
I've learned a lot of valuable stuff from screwing off spending time following threads on this site, ha ha ha, and one of the things that changed the sound I was getting is setting the speakers out into the room a little bit, like two or three feet from the wall they're up against. It has to do with room acoustics, and from the dimensions of the room you described you have the space to fill it with great sound. The easiest way to think about it until you understand room acoustics is that they need room to breathe. Especially if they're going to sit out in the room you want them to not look like a big box, to my way of thinking, to score high on what we call the WAF, which stands for wife approval factor, ha ha ha. It's actually real.
If you give these speakers room to breathe, you will be pleased with the sound. And they have two little knobs on the back so you can fine tune the bass response. When you get that right, if you have the right electronics feeding the system you'll literally be amazed because in most cases it'll literally seem like the various musicians are standing or sitting in the same room with you. The correct timbre is what you're after. Soundstaging and imaging is what I'm talking about and these speakers do it extremely well.
As far as electronics goes, you'll get lots of different opinions about what you should or shouldn't do and what you'll wind up choosing has everything in the world to do with what you'll be using the system for or more specifically, what you'll want it to do.
If you want it to do more than two channel audio it changes the game significantly.
You'll probably be able to figure it out with a certain degree of clarity by the bottom of the thread if you give these guys the right information. It was smart starting this thread! The speakers I'm referring to is the Martin Logan, Summit. I guess they have to sort of fit in your decor to look as gorgeous as they do in my place, but I live on the top floor of a high rise in an urban environment and I tend to prefer a more modern look so they're like wow.
I just checked this site and there's only one pair listed and it says no box, which means local pick up.
Oh, one more thing. I can imagine the things that'll be said about power conditioning and cables. There are naysayers, trust me. And they'll come out of the cracks on a thread like this. But when you have components that's capable of a high degree of resolution you will find that both of these things are what will male the difference b/w good sound and really good sound. OK, lemme have it Jason Bourne, haha ha ha.
By the way, there's two different pairs of the next model up from my speaker, called the Summit X and the reviews I read before I bought mine said that it performs even better than mine. For the budget you have, if you can justify spending more than 5K on your speakers it would actually be worth it to go for it. But I can tell you from my own experience that the Summit will give you what you're after in spades. Can't wait to hear what you choose. Have fun!