Here are my caveats:
1. The keyboard. Not the Touch Bar; the rest of the keyboard. There isn't much travel and I'm afraid it will aggravate my RSI. I've tried pressing the keys more gently, but sometimes I'm too gentle and miss keystrokes. Pressing the right side of the caps lock key is unreliable even when I press it fairly firmly. And the right shift key has gotten stuck once already. I'll give it some more time to see if things improve, but RSI is a deal-breaker. I'm considering returning the laptop.
2. The battery life. It's nowhere near 10 hours when I'm doing development. I haven't been keeping close track but I'd say less than 5 and less than previous generations. I think they used a processor which is more efficient at idle and took away a lot of battery to make it thinner. It's maybe not more efficient when working, so the battery life is reduced if you use the processor more heavily than they've anticipated.
3. The Touch Bar. I'm sure I can make it work, but I would prefer to have a physical escape key for vim, especially given that the caps lock key is questionable too so that may be out as a substitute.
4. That going from 1 TiB of storage to 2 TiB of storage would cost another $800, and the SSD is not even replaceable later. I don't want to spend that much, so I have 1 TiB that I'm already close to with photos likely to push it over. I really wouldn't mind having a 512 MiB SSD and a 2 TiB hard drive, but that's not an option. It wouldn't be as much of a problem if Apple Photos (or some other inexpensive product) had good support for auto-selecting part of the library to have on the SSD as a cache of full storage on a network/external/cloud drive. (I.e., one library that I could open up and add stuff to while disconnected, view some recent / starred / non-hidden photos while disconnected.)
5. 16 GiB of RAM rather than 32 GiB and not expandable. I gather this lost a three-way battle with battery life and thickness/weight.
Most of these (#1, #2, #4, #5) are the negative consequences of Apple's anorexia.
Having only USB-C ports isn't a problem for me. Losing MagSafe makes me a little sad—it has saved laptops for me—but I like the idea of being able to plug in just one cable to do everything. Those docks don't actually exist yet, but they will soon. In the meantime, I have the included power adapter, a USB-C to DisplayPort cable, and a portable USB-C to three-port USB-A + gigabit Ethernet hub. It'll do.