I'm looking for an alternative to pin headers and DuPont connectors for board/wire/board.
I've got reasonably competent at assembling the plugs, but I still find they're disproportionately time consuming and fiddly as *****.
Any suggestions for something that provides a similar function but is quicker and easier to assemble, especially when (eg) 10 pins wide?
For signal (not power) wires my first thought would be IDC connectors.
I had a similar quest. I settled on 2.54 IDC, which are cheaply available and quick to make. They also make good board-board connectors.
However, the cheap variety are dual row, which are not breadboard friendly. You can get single row IDC connectors but they are less common and tend to be more expensive.
Well if you have more money that time, then just buy premade cables.
Stack the boards. Male headers on the top board, female headers on the bottom board. It was called PC100 in the early 2000s, but has disappeared.
Would that rule out a regulated 5v feed for (eg) an Arduino Nano, a Bluetooth board, an SD card and an I2C GPIO expander?
That looks like exactly what I'm looking for 
... if only they didn't seem harder to find (in the UK) that unicorn manure. 
Those are low power devices so you can feed 5V through the connectors. My comment was more for motors, solenoids and so on. You can check how thick the normal flatcable is and look up the current rating.
How difficult can it be. Search your favourite supplier for IDC. A quick web search gives e.g. https://uk.farnell.com/c/connectors/idc-connectors
Sadly I've spent all the available budget on getting someone else to design and fabricate the rest of my project. Admittedly, if I hadn't been naive enough to spend money on DuPont connectors, I might have had the funds left to pay for some Chinese kid to make me a 2 inch 1x3 m/m connector or a 4 inch 1x15 m/f coonnector at the drop of a hat. I suppose I could reduce my Getting My Xxxx Wiped budget, but, as I'm sure youd agree, that just feels like one of life's essentials.
Nice idea, but as I'm CNCin my own single sided boards, that's not going to work on my current project.
Thanks. I'd failed to find what I was looking for from a couple of suppliers, but not Farnell. Will have a look. 
(And in my defence, I've subsequently found that I had misunderstood how the terminals get atttached on some connectors and, since the datasheet made more mention of whether or not they could be used in nuclear instalations that how to fit them ... well ... every day's a school day. 
)
Well I have used the single row IDC connectors. Without the right tool you can spend some time trying to seat the wires correctly.
I tend to buy bulk to get lower unit cost.
UK Sources,
Farnell / RS - reputable but may be pricey
ebay/Aliexpress - cheap, never had a problem with quality
Also Toby, good value, since they increased MOQs I don't use so much
You can also get ready made cables for some popular pin counts to save time.
If you crimp your own IDC connectors, I recommend a suitable tool, although a vice can also work.