By the way, I used some of the information in the article to do my last MAME build. While I know a lot of tricks with the Pi, I definitely learned some new ones.
I didn't use the instructions completely. I wanted to automate the build / patching process on mame to work with the Pi4 though, and the instructions work really well for that, but it requires some serious attention to sort out what parts of that article are about compiling a solid version of mame vs all the other stuff that makes the "appliance" part.
In the end, I have a working copy of 225 running on a Pi4. Without overclocking, 225 runs over 99% speed without frameskipping on games like DigDug and Galaga. I just wanted a version of MAME that has the output system that will work with LEDSpicer. I started with MAME v 189 and manually applied the patch changes (since the suggested patch doesn't work on versions that old), but it still chokes at the linking stage after compiling, due to some requirement for X11 that's buried in the MAME code somewhere... I ended up just trying to see if a modern MAME version worked well enough, and 225 was fine.
Anyway, based on my experience, the only thing I'd add to that guide would be a really obvious subsection that strictly deals with MAME compiling for anyone else that isn't looking for the full appliance experience. I think the automation script for downloading, patching and building MAME is really solid and is really valuable information just by itself.