Each port provides 5V/1.5A; enough for multiple USB-A peripherals on a single port with a USB-C to multi-USB-A. (I have a LG 5K and I use a keyboard, mouse, and microphone on one port; it works great) And USB-C speed (5 Gbps) will not bottleneck data transfer in that case.
I agree for the low bandwidth devices you've mentioned it's fine to hang everything off the one line. There is of course a speed hit for higher bandwidth needs[1] e.g. RAID arrays but that was true for the previous gen too.[2]
Nevertheless I still find it a shame we lost the variety of integrated ports from the previous gen. If we have to buy extra dongles anyway I'm equally ready to check out competitor panels.
AFAIK the LG 5k is the only panel offering 87W power output, right?
[1] http://appleinsider.com/articles/17/01/07/review-lg-ultrafin...
[2] http://www.macworld.com/article/1163773/storage/thunderbolt-...
Worst case for super-high-bandwidth devices you can connect directly to the laptop. (I do not have a external drive bottlenecked by the 5 Gbps limit yet, but may get an external SSD soon / eGPU once that is viable)
> AFAIK the LG 5k is the only panel offering 87W power output, right?
Currently, that is the case. The LG 4k only has 60W output.