Try Weber and Ringo’s Empire of Man series next. It starts with March Upcountry. Aliens, but not BEMs.
I mentioned Shelley earlier. Damn shame there will be no more books.
I noticed when I read it that it wasn’t at all graphic. But it was good, so who cared. 
Yeah, he had some good stuff. Just as long as you stay with the DRC books. His next series only had the first book and a half done when he died, but someone else wrote more in it. Not as good, IMO. But finding the books shouldn’t be hard, an Amazon search had lots of results, for new or kindle even.
The Metxadan stuff wasn’t a hit, although I agree it was very good. I don’t know how easy it would be to find, my copies are all used, and that was when Rosenberg was alive.
At least the DRC stuff was finished. When I talked to Shelley before Colonel came out, he said people kept talking about the last book General. But there wasn’t going to be one, because the DRC General never left the planet, so there was no story to tell. I think it actually irritated him that his readers didn’t realize that.
Three seperate but linked space marine trilogies set over a long timeline from the near-future onwards.
Plus a nearly finished (book 3 out next month)unrelated to the above space combat series.
I enjoyed both series. I’m especially enjoying the Star Carrier trilogy. They have a bog standard ‘hyperdrive between systems’ setup. After that however there’s heavy emphasis on relatavistic weapons and their implications.
How is that military SF?
Well, Mars is the God of War.
Thats actually a pen name of William H Keith, Jr.
If you want to dip your toes into another genre, you might try the Black Company novels by Glen Cook. It’s fantasy rather than scifi, but it’s a great series from the point of view of the poor bastards in the trenches.
Or try Grunts by Mary Gentle. Basically a band of orcs stumbles upon a cache of modern weaponry and become Marine Orcs. There are no good guys in the book, but it is an excellent read, and very amusing in places.
Apparently an outlier, but I highly recommend Downbelow Station by CJ Cherryh. Not really focused on the details of combat, but more on the political and civil consequences of interstellar war and revolution. Absolutely brilliant IMO. And still lots of action too.
I’ll second Boyo Jim on Downbelow Station. And I’d say the same for most of Cherryh’s Alliance-Union Universe novels (but not Cyteen). I’d recommend her trilogy called The Faded Sun, as well, which has aliens but not BEM’s.
Bujold’s Vorkosiganverse series. If you’re reading the CoDominium stories, don’t skip The Mote in God’s Eye. Roger MacBride Allen has some good ones as well: The Torch of Honor and Rogue Powers (collected into Allies and Aliens, even though they are both full-length novels).
Oh, forgot about Stirling’s Draka books. It’s not 100% military-oriented, but quite a lot of combat in it.