I spent a short time at a boarding school as a teenager (my choice) and while it was not at all a bad place to be, and would certainly have represented an excellent alternative to a problematic family life, there are still some points that make me grateful that my main education was at home:
I thoroughly enjoyed family conversations round the dinner table at night- the thought that I might have missed out on 11 years of those conversations is unbearable. No boarding school teachers would have had the time or interest to talk to me like my parents did.
I am still really close to my brothers; we are very different people with different interests in life, but we have so many shared memories.
I was involved in the day-to-day running of a home, including the balancing of a family budged, cooking and cleaning, parenting of younger children- these skills have stood me in good stead later in life.
I also realise I have learnt a lot through being able to observe a (successful) marriage at close hand over the years. Harder to do that at boarding school.
I had a lot of freedom in moving around our local area, cycling and walking: I really wouldn't have wanted to have missed that. At boarding school, even at the age of 16, we were only allowed out for short walks in the company of another teenager.
There was a lot of anorexia at the boarding school (despite it being a really caring place); I am glad I didn't have to spend my time with that much pressure on me.
There may be lots of activities in a boarding school, but I and my brothers kept ourselves very active anyway at home.
Educationally, it was not really any better than my state school, but at home I was able to draw on my family's educational resources.
I feel the same about my own dcs - not that boarding school is necessarily bad, but that what we have to offer at home is pretty damn good: I don't feel we need to look for an alternative. Which is just as well, as we wouldn't be able to pay for it anyway