That's an interesting approach to BGs. Very similar to classic strategies for a nice reese. I'd be a little concerned at the overlap of frequency ranges when using EQs and may prefer filters.
I shouldn't have used the word "loudness" cause that's a loaded term. What I find with my songs that use tons of reese automation is that one bar may have the right EQ and sound "pleasant" while the next bar is harsh - so instead of loudness, I'm really just hoping to smooth out the balance of different frequency ranges between complex automations...which may result in some extra headroom or at least perceived "loudness" or "warmth".
I haven't tried it yet, but my plan for the drum buss would be to compress and turn up the 80-300Hz range for more thump, and then apply very little or no compression to the rest of the ranges to maintain "snappiness" with the possible exception of the 8Khz and above region that I'd really like to experiment with.
And I couldn't agree more about the issues with loudness, it just drives me crazy as, at heart, I'm in love with limitless acoustic sound or analogs. One thing that is separate from loudness but similar is the "relative loudness" the way that fuller, well EQ'ed, and well mastered tracks sound. Hell, for all I know some folks are simply pushing limiters and saturating with soft clipping...and sometimes that sounds good to me which is why I'll never be a mastering engineer.