Power points / cig lighter sockets / hella sockets.
How many in your truck? How many would you like? Where should they be?
My current truck has one socket near the bunk: good for charging phone over night.
One 12v and one 24v in low level central tray, plus one USB point. All these are below the cup holders! I dont use the cup holders as such, but seems a dumb location to me. Not saying 12 or 24 volts is going to electrocute you if your coffee spills, but putting elec equipment under coffee cups is not good. Id like 2 or 3 more sockets on top of the dash so cables dont dangle everywhere. Do not many of us have phones, tablets, sat navs, cameras (pointing outwards) wed like to keep charged? And please, a tray on top of the dash with perpendicular sides to stop things sliding off, rather than being launched up the “artistic sculpted organic curves” given us by fashionistas.
If a truck manufacturer was to ask me my opinion, I’d say that a decent (e.g. 2000w) mains inverter with three-pin sockets should be a standard fitment to new trucks in this day and age.
For me, as Harry says, a 2000w inverter, with a socket in the top lockers for a microwave, and one by the seat for a lap top or a kettle etc. They should be powered off a solar panel on the roof, to help preserve truck batteries. And at least 2 USB sockets on the dash for a sat mac and camera. 12/24v sockets at either end of the bunk and 3 on the dash, like the Volvo, should be enough.
All the toys in my car are powered by USB plugs of which there are 5, but in the boot I normally carry a 300w inverter, if I aint left it in me shed !
I just fitted one of these for a tenner 
Yep, I like the idea of inverters as standard. Pre wired microwave fitting excellent. And Drifts little gizmo looks neat. For myself summat similar should be fitted on top of the dash, at the front edge, by the windscreen, so cables don`t dangle.
Manufactures are not going to fit them because they will have no end if battery trouble
GETTING:
Manufactures are not going to fit them because they will have no end if battery trouble
Inverters normally shut down if the input voltage gets too low, but my narrowboat has separate batteries for the starter and leisure circuits so that the boat will always start even if the leisure batteries have been run low, it can’t be beyond the capabilities of truck manufacturers to do something similar.
Split charge relay, problem sorted 
My DAF has one 12v and a Hella 24v, but I don’t know whether the Hella works, and I don’t want to waste £20 on a kettle to test it. 
I think realistically, in our world of technological fixes, a new truck should have at least two 12v sockets, and two USB sockets. I have an adaptor with two 12v sockets and two USBs, and I find it perfect for everything I need.
I think if your truck had seven power points, you’d get people trying to cook a full-English simultaneously. Electric frying pan, microwave, boiling a kettle for the pot of tea, telly on, fridge on, sat-nav on, phone charging, iPad charging, laptop charging through an inverter… Enough electrical appliances to send your meter at home through the roof. Then the whole system goes bang, and people start moaning that MAN, DAF, Scania electrics are crap, or the next poor sod has to make do without a sat-nav because the ■■■ before him’s blown the sockets.
Be good to have something up top by the sun visor so sat nav could be up out the way