I'm a 100D/SL1 user who had sworn off upgrading to an SL2...
...but then Canon gives this body series all these big and small improvements that add up to a very solid upgrade:
* Fully articulating screen -- Totally unexpected in this smallest DSLR body. Useful for those angles difficult or impossible with the old fixed screen and for that holiday two-fie. (I'd also imagine this small-body tilty-flippy coupled with DPAF would make it popular with many in the vlogging crowd.)
* DPAF -- Was a possibility but not sure they'd trickle it down to this level. Definitely a welcome addition. I'd have hoped for a 19-point all-cross-type DPAF from the now around 4-year-old 70D (after all, the 77D/800D got 45pt DPAF) but guess Canon wanted to keep it very entry-level with the AF points. It's still DPAF, which has in recent years distinguished Canon's line-up from the other brands.
* Other useful things like a bigger handgrip (the old SL1 never slipped from my fingers but often hoped there was a bit more to cling on to),
60p HD (never expected 4K at this level) and electronic IS might help when used with the small non-IS primes,
wi-fi (with its own quick access button),
and of course the higher-res sensor and slightly faster shooting speed.
The next-up 800D and 77D are only slightly, but still noticeably, bigger and with their added features would probably be better options for many, but for those looking to stick to a DSLR in this form factor, Canon's done right mostly with the 200D/SL2.