The Holst has been something of a goddess in my kitchen from the start. Her recipes are so sensible and practical and child- and budget-friendly. Two things I will always do with one of her recipes, though: halve the salt, and double the spices. I up the seasoning in most recipes the second time I make them, to be honest. When we have Meals out with Russell, it's becoming a tradition (which I will encourage) to get Indian so he and I can have Super Spicy Dead Animal, and everyone else can wimp out in their respective ways*.
Anyway, what I've learned over the years is the importance of getting the roux just right. Dark but not too dark. There's really nothing else to this except constantly tasting during a long, slow cooking, and adding more paprika and thyme every time you taste.
The great thing about this is that a) it feeds our family on about 300g of mince, and b) soup is a great way to get kids to eat veggies, should that be a problem. It actually never has been for us. But then, I've never used the phrase "you have to eat your vegetables."
* These days a quite startling number of our friends are vegetarians, something I have absolutely no problem with. It's not actually a bother accommodating that, it'd be fucking rude NOT to. But I will eat dead animals in front of you. My main problem is that nobody else in my family likes spicy food.