Unfortunately the 60mm gets not too much love, without too many good reasons if you ask me (especially if the new software will improve its performance).
Even though I had ordered the 56mm, at the last moment I chose the 60mm over the 56mm because it costed a bit more than half than the 56mm ( and now less and there are lots of them offered secondhand) because I am a cheapskate ( who had just bought a X-T1 and a 10-24mm though! ) and because the close up performance was important to me...rather more than the “ bokeh” of the 56mm ( the spelling checker doesn’t recognize the word! ) would be.
I don’t particularly agree that the 56mm would add any particular detrimental distortion, but I have made many portraits by using the 35mm too, so I am biased.. but as always to each his own.
If one can live with the limitation of adapted lenses you can find just about any focal length that you would wish to want to use. If you are a “ bokeh” lover... ...you can use adapted lenses at the maximum aperture and do not bother about anything else ( well except for manual focussing )
Unless you're going to shoot the 56mm at f/1.2 all the time, forget the APD version. It's very slightly smoother at f/1.2 at the cost of nearly a third of a stop of light. For f/1.4 there is almost no difference and at f/1.6 onwards it looks no different to the regular 56mm and you're still losing a little light. If you ever talk to people from Fuji, even they will tell you the APD is pointless unless you're glued to f/1.2.
So, 56mm vs 90mm. Same as 85mm vs 135mm for 35mm sensors, I personally always wish 85mm lenses were a touch longer and 135mms were shorter, so I typically end up using 100mm-105mm lenses or their equivalents. Sadly, Fuji doesn't make a 100mm equivalent yet! Generally, 90mm is going to be good for headshots and, if you're outdoors or in a really huge studio, you're going to be able to back up enough to get a waist-up shot. Don't bank on it for much else. And, if you do have that much space available, the 50-140mm f/2.8 gives you even more subject separation, anyway. I used to have a 135mmm lens on a full frame Canon body and I sold it pretty quickly because I found it was always either too long to use or, when I did have the space, the 70-200 zooms did a better job anyway. The 56mm is good for waist-up and can do full-length if you have the space. For tight headshots it introduces a little distortion, so only risk that if your subject has very well-proportioned features. Your typical professional model is going to look fine in a 56mm headshot because they're probably going to have the features to get away with it. Your average family shot is going to be fine because nobody cares about a little distortion there. Anything between, it's going to be distractingly unflattering. Again, I wish Fuji would make a 100mm equivalent.
Really, the 56mm and 90mm are going to work best as a pair, or you just grab the 50-140 zoom. If you are only going to have one lens, the 56mm is more useful—lighter, smaller, can work with less light, and you can always shoot wider then crop in for a headshot—but it's definitely a tough call. What one person calls a portrait, another may say is too wide to be a real portrait, or they may complain it's too tightly-framed. If you like wider, the 56mm is definitely the way to go. If you like tight, the 90mm is worth considering but is still hard to recommend. Usually, the people with the space and career to make full use of the 90mm will be better off with the 50-140 anyway. That's not to say there aren't exceptions here and there, but, for most people in most situations, the 56mm is going to be the more useful of the two.
If you have an X-T1 or will be buying an X-T10 then I'd also consider the 60mm. It's just that fraction tighter than the 56mm, enough to make headshots not quite as unacceptable, while still being significantly wider than the 90mm. You're giving up a lot of speed to the 56mm but not much compared to the 90mm, and for most closer portraits you'll probably be stopping down, anyway. And it's still faster than any portrait zoom. The 60mm does focus slowly with other bodies, but on the X-T10 it's as fast as any other Fuji lens and the X-T1 will be getting a firmware update which, I would hope, will also bring the 60mm up to speed on that, too. I wouldn't bother looking at the 60mm if you have a X-Pro1 or X-E camera, though, as the focus is just too slow on those.
