Great learning tool if you dream of building your own CPU architecture:)
Try it!
I cut my programming teeth on an Acorn Electron (a somewhat cut-down BBC Micro) then later a Master128. The fact that the BASIC ROM included a decent multi-pass assembler was great for learning the deeper workings of the machine and such things in general. Being able to easily mix BASIC and assembly provided good lessons wrt choosing where optimisations were worth bothering with and where you should just stick with BASIC to save dev time. Those machines were also based around variants of the 6502.
So the BASIC ROM was not a lost 16KB of address space if you were only using Assembly.
Though the main two reasons I had for assembly were faster maths loops and graphics (via direct access to screen memory including, on the Master, the shadow screen for double-buffered drawing), so neither of those parts where sometime I called much.
Was always jealous of people who had that available to them, and that it was built into the BASIC of the BBC machines is pretty cool. Even the monitor program built into the Apple II was superior.
I was lucky in that my elder bother did the research and my parents (who paid for the things at the time) saw the wisdom and spent the extra on the Acorn machines, that were best educationally (while falling behind considerably wrt the availability of games, despite being more than capable enough alongside other popular machines on the market), despite the extra cost (which for my parents at the time, though I didn't realise it back then, was a very significant issue).
That sort of “investment” in us kids, and general encouragement of our interests, by our parents did a lot for us, me in particular (by luck rather than favouritism: I was just the most techie minded of me and my brothers, they invested in my younger brothers interest in music too), long term. They didn't have much, but they made every effort to make the most of it for us.