While I don't have the X100S or T, I did get an XE-2 last winter with the same general concept. I got it with a 35mm 1.4. Until this weekend, that was all I invested into the system, one camera one lens in a much smaller package. It was a huge help keeping the initial transition simple. There were a number social events that I brought it with me and it was simpler, there were many family trips I brought both and felt limited by the one lens and ended up pulling out the DSLR. But any photos of people, the Fuji had some magic I just couldn't explain. The experience of using the camera, with the EVF (which the X100 has btw), and getting instant image feedback is great, there is no guess as to how the light meter is interpreting things. And it's very easy to preset the camera, so that you can go for what you know you want before turning the camera on and bringing it up to your eye.
Last month was a watershed moment for me, for Thanksgiving we traveled about 400miles to go and visit family, I had a camera on me the whole weekend and it was the Fuji, I never edited a photo on my laptop, it was all over wifi into snapseed then up to social media and my website. We got home and I realized I did not take the DSLR or any of the other lenses so much as out of the bag. I had a camera on me the whole time. My editing workflow was quick and didn't peg me behind a computer screen for hours away from everyone. After that I started talking about my camera like David Hobby, all the sudden it was my mistress not my camera (link to video of him talking about the X100s, there's also a video from Zack Arias there worth watching: https://www.youtube.com/watch?v=omL9HOudSwc )
The 35 without the lens hood kinda fits into some of my larger pockets, I'm starting to eye some pancake lenses to make it a true always with me camera. Recently added the 56 for portraits and times I want to have more distance, and well the low light and shallow DOF are amazing tools. 3 primes and 1 body will still be lighter than a DSLR and the 2.8 zoom covering the same range. But even the Fuji and the 35 beat the 5D and 50mm for convenience and match it for image quality, and in some respects exceed it. And I gave it a year on one lens, suppressed the GAS and let the fixed medium prime teach me. I keep the DSLRs because I shoot sports and so my AF comparison often shows the Fuji at a disadvantage, but I'm able to take the Fuji and get at the level of children and have it keep up without much worry, but an occasional missed shot. I pretty much leave my camera in the M AF mode for manual focus and have the Fn Keys setup to allow back button focus and so even the AF carries over well for me.
Oh and you can bounce the OCF if you forget your speed light and it works with my $30 yongnuo radio triggers and skyport system. You can move the Fn keys and set several buttons to do any one of a few dozen features just like in the Canons but with words instead of symbols. If you have any specfic X-E2 questions I'm happy to answer them (and if I miss this thread updating feel free to PM me)
Here's a link to those Thanksgiving weekend photos (straight out of camera or minor snapseed adjustments, no LR or PS) that changed how I saw the camera, but also show how it does in an at kids level situation:http://www.dcanavanphoto.com/p196409836
I have a friend with an X100s, it's really nice. He has some conversion lenses. The leaf shutter is amazing, and it works well for him. But by itself it's not what I was looking for but with the right set of lenses on an X series camera, I could see it complimenting the system nicely for how I work.
If you're going Fuji I'd decide what features you want, then once you know based on feature set if you want X-Pro,X-E,X-T or X100, go with the newest version in the line. The changes made in the updates are there because photographers say "It's great but I wish it did this...." and Fuji listens. They also support with multiple and frequent firmware updates adding features, the newer the line the more they're usually able to incorporate (eventually adding feature support ends on anything but this way it's prolonged, the X-pro is about 4 years old and just had a new feature added last week though). And make sure to get an aftermarket strap if you'll use one at all, and have multiple spare batteries; if you're a Lightroom user, may need to check versions to make sure you're up to date enough for the RAW converter.