Based on these factors, If this were me, I would probably buy a used entry level Canon or Nikon DSLR (I know you don't prefer used but bear with me). Amazon Warehouse Deals has some really killer prices sometimes. The kit lens plus a cheap tripod can be just fine for architecture and cityscapes. The rest of the money can be spent on a 50mm f1.8 lens which can take full body shots just fine, all for under $750.
Architecture and cityscapes can be taken at f8, and at f8, "kit lens" is comparable to "good glass". Nikon or Canon's 50mm f1.8 is a good, value prime lens with decent image quality at wider apertures to take pleasing portraits.
I know that doesn't involve any of the potential cameras you're thinking of, but that kind of setup is what someone involved "in the long haul" should be starting with, in my opinion.
If you're going to recommend something completely far and away from what he's already looking at, usually you should give reasons for why you're ignoring what he's narrowed it down to. Especially when all you have bolded is "good glass". The mirrorless systems have great glass too.
Diddy, few things to keep in mind:
If you're doing lots of architecture and portraits, you're going for relatively static subjects, which I'd say opens the door for cheaper, older vintage glass that's manual focus. That can save you a lot of money in the long run, though you'd be giving up autofocus. Every mirrorless system you've mentioned is compatible with every vintage mount.
M43 has the advantage in sheer compatibility -- there's multiple manufacturers to choose from, so if you like the lens but not the body, there's other manufacturers that might make something closer to your preference. *BUT* the M43 sensor isn't as good as APSC... You'll get less bokeh, and more noise, especially at night. (This is generally speaking) I hear Olympus's lenses are really nice.
Fuji vs Sony, Fuji has better JPEGs, but Sony has better RAWs. So just ripping em off your camera and throwing them on the net, you'll get better results on a Fuji, but Sony will give you more sharpness and detail when working with RAW than a Fuji.
As for pure handling, I'll have to give it to Fuji. They tend to style their cameras off of old film cameras, and have dials out the wazoo, where Sony is known to be a bit clunky with their menu systems. FWIW, I shoot Sony, and the menu is a minor nuisance when you've set your camera to have 90% of your options without going into it.
Sony is the only one right now with a full frame upgrade path. Dunno how important that is to you though.
