Do you have/want/regret/don't have children?

I can not give a definitive answer to this, as it depends from which view I look at it from.

The unselfish view is no, I do not regret having children.   I made a decision in the mid 70's that I would not have any because I didn't like the way the world was changing.   One thing in particular that made me arrive at my decision was that the so called "experts" predicted an Ice Age by the year 2000.   Fortunately, this was one of many reasons the others were political and social.  I also thought the world was becoming over populated and would only get worse exponentially.

The selfish part of me says yes I do regret not having any.   I am now in my early sixties and have no family of my own left and I dread this time of year.  

However, I feel I made the right decision because I do not like the speed at which society is changing.   The 'I want everything now' attitude is only going to lead to wrong decisions being made.  I also think advancing technology, especially robotics should be slowed down and more thought given to how these changes could actually make life harder.

There have been a few studies on this subject and it appears that there isn't a great correlation between having children and happiness but the evidence (for most countries, but not all) is that there is a slight decrease in happiness for those with kids.
Personally, I have four girls and there has been a mix of both pleasure and pain. Overall I'd say the pain is winning sadly.

People with children will probably have less time to reply on this thread...

I have 3 (oldest is 6, youngest is almost 1). No regrets. I haven't really given much thought about children until my wife's clock suddenly went off when she was in her late 20s.
Life changes drastically, as everyone knows, but i am not sure everyone realises to what extent exactly until you have your own. I don't know anyone who regrets this decision after having them (at least not in the open). I could also not imagine having regrets. The only regret that creeps in from time to time is the general feeling that the world is too cruel for them (even though relatively speaking, we are all incredibly privileged living in the developed world) and it seems that they should have some sort of say beforehand, whether to exist or not (sorry, I know this sounds insane).

I also don't think it is possible to make a rational decision (at least not for me). It was 80-90% an instinctive decision from my side if I try to be honest because there are too many variables to even begin to rationalise it. It just felt 'right' to have a family qhen the time felt right. If one cannot afford them, then it is perhaps an easier decision (but even this is is difficult to quantify and take into equation).
By the time I was around 30, I was financially free (meaning, I didn't have to work to pay for our outgoings as income from investments covered everything) but I continue working anyway. My wife mostly takes care of the kids (and works part time). We never inherited any money.

With kids, the outgoings seem a little less predictable now (with private schools/universities etc, depending on what path they chose). My main worries are any potential health issues of the kids (or our own) and losing contact/become estranged from them for whatever reason later in life (I am very sad to hear this is the case for some, not just on this thread but realise it happens quite frequently in general). I need to try and keep our financial situation hidden from them to make sure they make their own way in life. I don't know if this will be possible though and plan to give it more thought when they know how to 'hack' into my computer/documents.

Everyone's situation will be way too individual to give any meaningful or useful advice even though it might seem like there are aspects that need considering...I think in the end nobody has a clue whether it was a net benefit overall or not, after the fact.

Coming at this from the other side...

After a week with my early-stages Alzheimers father staying, if anybody's looking to increase their personal responsibilities, he's available at a very reasonable price...

Through my 20's and early 30's I earned good money, traveled a lot, enjoyed life and did whatever I damn well pleased within reason. I wasn't that interested until about 35. After having them I look back and my life before seems quite shallow in comparison. I have found that having young kids is harder than I think someone without them can really understand as it robs you of nearly all of your free time and personal space. But I'm happier now than I was then and wouldn't change a thing. I think it must be some kind of biological switch we have evolved, because looking at the two scenarios objectively it doesn't make any sense to be happier with than without. I still can't wait to get some of my time back once they are older though.

EDIT: Additionally, my investments have nothing really to do with the kids. Obviously I want to leave them something but I think that they will get a lot more out of life by making their own way. For me investing is just setting myself and my wife up for retirement, and a bit of a hobby.

Three girls - and the pleasure has been immeasurable.  The pain only comes when they are adults and it is only occasional - could never wipe out the pleasure from their childhoods.   I never trust these studies which try to measure happiness.  I have a brother, with a partner,  no children, who claims he is happy and independent.  Can do what he likes. And what does he like doing? Counting up his assets, watching his shares, seeing his net wealth increase.  A veritable Scrooge.  Well, he does like a break at a Warners Hotel, God forbid!