It's great to read a recollection by someone from the UK of a similar age to me. I remember the Jupiter Ace very well and was so interested in Forth that I got the Acornsoft Forth ROM for my BBC Micro. I too made money selling software (and writing magazine articles---mostly about the Research Machines 380Z/480Z).
I think the biggest difference between then and now is the sense of discovery. I spent an enormous amount of time just discovering everything I could about computers and the machines I had access to. Everything from circuit diagrams to compilers. I don't think there's the same level of discovery now because so much else is available. In some ways, a lot of what we could do with a computer was understand the computer itself because other stuff (like games or programs to buy and run) was relatively difficult to get.