Well, it depends if USB-C takes off or not. I think it probably will... but then FireWire was going to be a winner once it got adopted as the standard for DV camcorders, wasn't it...?
I've counted them. Twice. And I'd need about £400 worth... or £500 for a neater solution with docks... and that's with the discount and still not replacing the USB-C to B/micro-b cables on every last device I might use. Currently, I don't need to shuttle my MagSafe power supply to and from work, because I've got an Apple Cinema Display with Magsafe at work, so for the same benefit that's £100 for a new USB-C PSU and charge cable (actually it makes it better value to get a £150 USB-C dock... if that turns out to be compatible). The ACD needs a USB-C to MiniDP adapter, but the only one I can find on line has lousy reviews, so that would end up with a fugly USB-C->DisplayPort->MiniDP double-dongle. At home, I need 2 x DisplayPort and wired Ethernet... On the road, I need VGA, and a USB-A for dealing with memory sticks... but HDMI is starting to crop up so that's both the Apple AV dongles (maybe there's a mini hub/dock with both, if it is compatible, but it won't be night-and-day cheaper).
Until you've sat down, thought through what you actually need, you might be surprised at how quickly those £10s, £20s and £30s for "just a new cable" add up. Even with the shiny new LG thunderbolt 3 display you'll still need extra cables and dongles, because despite having tons of space they couldn't squeeze in a USB-A or Ethernet port...
They do add up, I get it.
But you start out with "need", and the first (and most expensive item on the list as far as I see it) is a second power brick and charging cable to the tune of $98 (I'm going to use USD pricing because that's what is available to me, but I totally get that things may not be priced even remotely the same in your market). This is a convenience, and a minor one at that given the mass and volume of Apple's adapters these days, not a strict need. I do understand the value of that convenience, and that you've grown accustomed to it, but it's certainly more of a deferrable purchase. Your ACD cost a lot more than £100, and you've already gotten many years of usage out of it. You can still use it as a display and USB 2.0 hub, and it will continue to charge your current laptop just as it always has. There is a certain point where a device's compatibility with the current latest and greatest begins to wane. If not carrying that little brick back and forth to the office is worth $98 to you, then buy it, if not you can hold off.
For hooking up the ACD, you might want to check out the
HyperDrive USB Type-C Hub with Mini DisplayPort (for 2016 MacBook Pro & 12" MacBook) for $49.95.
Then you say, "and
still not replacing the USB-C to B/micro-b cables on every last device I
might use." You don't need to. In fact, you shouldn't. For all the stuff you currently use USB Type-A for, you can get a decent USB Type-A hub with a single Type-C connection for the MBP. No new cables or flash drives required. I'd still probably grab one of the Apple USB-C to USB Adapters at the $9 price, because they're wee and would probably come in handy. I guess I'd also pick up a Type-C to Micro-B cable for mobile devices (and/or Type-C to Lightning if you're in that camp) for when you're on the road and using a hub would be inconvenient.
Turns out the Type-C to DisplayPort cables are still rare creatures and a bit pricey where you can find them. Do you really need two though? My DP displays are the daisy-chainable kind, so only one would need a Type-C cable. I cringe at the thought of connecting anything these days with VGA, but whatever—projectors last forever I guess. A good quality HDMI 2.0a adapter I can get behind though.
So by my tally:
Apple USB-C Charge Cable (2 m) $19.00
Apple 87W USB-C Power Adapter $79.00
Hyper HyperDrive USB Type-C Hub with Mini DisplayPort (for 2016 MacBook Pro & 12" MacBook) $49.95
Belkin USB-C to Gigabit Ethernet Adapter $26.00
Apple USB-C to USB Adapter $9.00
Apple USB-C to Lightning Cable (1 m) $19.00
Anker USB-C to 4-Port USB 3.0 Hub $17.99
Belkin USB-C to VGA Adapter $29.00
Accell USB-C to HDMI 2.0a Adapter P/N U187B-005B $34.99
Monoprice Select Series 2.0 USB-C to Micro B Cable, 3ft $8.99
2x Google USB Type-C to DisplayPort Cable $39.99 ea.
Grand total: $373 (and that's a lot of dongles)
Total less the Apple and Monoprice stuff which falls more under convenience rather than need: $238
And if you only need a single Type-C to DP cable: $198