The trouble is that so many marriages do not go the distance. Then what happens to the kids? They get to see one parent regularly who may well find the job quite tiring. The other parent, if the children are lucky, get to see the kids ones a week.
I can't remember what I was watching, but it had some interesting facts on marriage. Now this is all US-centric, of course, but from what I was watching 1 in 3 new (first) marriages fail within 5 years. 1 in 2 (half!) of all marriages fail in the same time frame. As a divorcee with kids, your point is absolutely true - as much as I love my son, there are times that I wish I would have put my ex-wife off when she was insisting on having another child.
One point that you forgot to mention, once the divorce is over the custodial parent (the one the kid(s) are with most of the time) can use them as a weapon against the other parent. I'm not saying that all people will do this, but mine certainly has. In my state, the standard visitation is every other weekend (1st, 3rd, and 5th Friday to be technical) and changing that to accommodate non-standard work schedules is almost impossible. I work nights, and my days off are Friday and Saturday. During the school year, I am also supposed to have him on Thursday nights...which since I work at night presents a bit of a problem. I will say that I see him more now than I did before the divorce, but it's still very difficult to spend much time with him since I'm always either working, or trying to catch up on housework that I can't do during the week. I also have to find ways to afford an overnight nanny/sitter to stay with him while I'm working. All this because my ex-wife decided that I wasn't worth talking with, and she could use my son to get at me emotionally...seems she doesn't like the fact that I haven't come crawling back to her. [/rant over]
I think the school system in the states has gotten better. Because before they were just looking for a paycheck. Now the parents and students demand better. And they have gotten better teachers. Who give a shit and are not there just to collect a paycheck.
At least here in my state, that's because teacher pay is really, really low. Seriously, what we pay our teachers is almost criminally low IMO, especially given the tax rates here. The only people you have doing it now are people that do it because of their passion for teaching, not for the tiny paycheck.
*Snipped for length*
Here in the US, there is still a need and paths for skilled tradesmen/women for various jobs. The problem is that the university system has pushed the idea that a degree is everything so hard, especially with HR staff, that now everyone thinks they need a degree when they actually don't (probably). Most of my peers around my age think that a degree is their path to untold riches and wealth, and an easy job where they can just collect a paycheck. I personally did not attend university, and have earned my education the old-fashioned way: I found what I like to do, and taught myself what I needed to know. I'm now a Senior Systems Administrator, making a pretty good wage, with only about $10k in education debt that I'm paying off as I can, and didn't really need in the first place. I got suckered into a training program that I could have done myself, but at least I was able to leverage it in to some industry certifications. Most of my peers are just finishing their degrees, or finished them only a few years ago, and are making half or less of what I do now.
The lack of a degree does hold me back a little bit, because HR staff don't know what IT entails, so they just go looking to check boxes before forwarding my resume/CV on to the hiring manager. Since I don't have a degree, I can't check that box, and don't get forwarded very much...but every once in awhile I get lucky and have a hiring manager that doesn't care. I'm far from alone in my field like this, but most people aren't willing to put in the hard work and self-education needed to be able to do what I've done. Which I don't really mind, since it means demand for my skillset is almost always there, and I've never been out of work for more than a couple of weeks.
So, the long and short of it, in the US at least, is that these career paths are still there. You just have to look for it, be willing to put in the work required, and be persistent in chasing your dream. That is the major stumbling block, most people don't have the fortitude anymore to do what needs to be done, they just want it handed to them. One of my favorite minor celebrities, Mike Rowe, has actually started a foundation to help folks that want to learn a skilled trade, because there is such a shortage of skilled tradesmen here. Not to try and shill for him, but check it out:
http://profoundlydisconnected.com/foundation/