Second, you really do have to think of the new MacBook as an iPad design brought to the laptop.
But why is that a sensible thing to do? One of Apple's successes thus far has been understanding that tablets are tablets and laptops are laptops, while its competitors try and fail to do both.
The point of a tablet is that you can use it hand-held like a book, while moving around or lounging in a comfy chair. Connecting even one cable to it ruins that. When my iPad's battery runs down, my inclination is to do something else while it recharges. You sacrifice a lot of precision and functionality in the UI by going touch screen - but attaching a keyboard wrecks that hand-held portability.
The point of a laptop is it has a proper keyboard, a more precise pointing device and more connectivity. You typically use it on a desk or table, so having it 'tethered' isn't such a big deal. With my laptop, my inclination is to plug it into the power wherever power is available so you don't have to worry about the battery, and don't have to have over-zealous display dimming and auto-sleep settings.
If you want a tablet with a keyboard, get a keyboard case for your iPad, or buy an Asus Transformer or MS Surface - so you can discard the keyboard when you don't need it. Personally, I had my iPad in a keyboard case for a while, but took it out when I realised that I wasn't using my iPad any more, because it made it more cumbersome and without easy 'comfy chair' use using a full-size computer was a nicer prospect.
The single USB-C slot in the MacBook only makes sense if you really believe the "all day battery life" claim, and if you wait for a decent range of USB-C cables and peripherals to emerge.
Apple already has other computers that are fairly lightweight if you need or want a larger screen or more ports built in. I realize that people are frustrated that the existing Air lineup didn't get a screen update, but it seems fairly likely that Apple will update the rest of their laptop lineup in the not-to-distant future in a way that will clear up their overall strategy.
accept that you may need to keep a lightweight adapter in your bag. It's really not that big of a deal - it's similar to carrying around a usb stick!
Well, actually, make that the $85 Digital AV adapter which includes a USB-C passthrough port for charging as well as a regular USB socket. Unfortunately, the HDMI port seems to be gimped and only does 1080p screen mirroring rather than the full dual display capabilities of the MacBook.
If you need something more powerful, get the 13" rMBP which is considerably smaller in overall footprint than the 13" Air, yet 'only' 1/2lb heavier.
Agree that the 13" rMBP is the new Air (and will probably replace it ~2016).
The MacBook would still be an infinitely better machine with a second USB-C, though (I'd have dropped the headphone port and sold a USB-C to headphone dongle).
Hmmm. So people trip over their MagSafe cable saving their laptop, but never seem to trip over a USB, DVI, FireWire, Thunderbolt.....hmmm. Quite a mystery.
Well, the USB/DVI/FireWire devices are usually on the same table as the computer, so those cables are much less likely to be trailing over the floor. Also, for a laptop, having the power suddenly disconnected is no big deal, whereas having a disc drive yanked out mid-write is not a good thing, so you have to balance the risk of accidental disconnections vs. cable trips.
Can't apple just continue to include an adapter like they do now?
I think the EU regs specify micro-USB (and now we're seeing why that was a stupid idea vs. just mandating a USB-A connector on the wall-wart so that the power supplies were universal). They're more likely to revise the spec to allow USB-C than Lightning - but knowing the EU, by the time the paperworks done, our devices will charge themselves from zero-point energy (or if the whole civilisation thing doesn't work out, a donkey on a treadmill)