Hi pwinwood and johnfron plus anyone else interested,
I decided to persevere with the DS-5 Community Edition, despite the fact that it does not include an/the ARM Assembler, and have now configured it so that I can:
* use DS-5 / Eclipse for DS-5 on my Windows laptop to manage files locally and on the RPi as a remote device (all you need is the RPi's IP address and to create a root password on the RPi for this)
* use MinGW for C/C++ development in DS-5
* use YARGATO and YARGATO Tools for Assembler development in DS-5
* create .o files on my laptop from e.g. .s source files that contain RPi-specific code, copy these to the RPi and then create executables on the RPi
* debug Assembler programs that are on the RPi through DS-5 on my laptop
* create executable files on the laptop from generic source code and then copy these to the RPi
* debug C programs on my laptop via DS-5 both when they are local or on the RPi
* the debug tool includes e.g. the ability to see the content of the ARM processor's registers
For anyone who isn't reading this and thinking "bug deal, I can do that already", please post if you think it would be useful for me to write a 'how to' on this.
I did evaluate NetBeans and BVRDE, pwinwood and johnfron, so thanks for the tips; I decided to persevere with DS-5 Community Edition because I like its look-and-feel (and because I liked the challenge, to be honest).