[Longtime Collector]

WYou mentioned earlier the limited capabilities of grouping as having ''artists group by genre'' ... but not album by genre?

Nope. The group concept was not developed with music library in mind, it fits the video db schema far better. Datawise all kinds of things are possible, but it doesn't slot trivially into the way grouping is currently implemented.
 

1) I'm guessing it would be difficult to do album group by genre (given there are multiple genres attached to each album)?

Multiple genres isn't an issue (artists have that too), the data aspect is relatively easy but the historic way that nodes and navigatation betyween then is designed is where fundamental change is harder.
 

2) If Kodi is no good for us singles music fans, can you recommend an app that can be accessed within Kodi that perhaps suits our needs? I would prefer to not have another firetv-level app.

Sorry it seems "no good" to you as a singles fan, it is just a matter of what previous and current devs have been most interested in. The smart filtering of Yatse might might let you navigate songs in the way you want, worth a try.
 

Who purchases albums these days anyway?

@Longtime Collector that would be me

Thanks for tolerating me for so long. I'll look around for another solution. Be safe.

Now that I've had some experience I can report that if you only have singles, fill in the album and albumartist fields with the name of the artist. This then allows you to use the generic music nodes for genre and year. The advantage is you can fill in albumartist for duets as artist1 / artist2 and get these duets listed with each individual artist. Kodi is great.