OK, here we go:
Bolo by Keith Laumer -read the original, not the sequels by other authors. Although
Road To Damascus stands up really well
The Weapon by Michael Z Williamson. Also,
Freehold by the same author.
A Talent For War, Seeker and
Polaris- all by Jack McDevitt, about a guy who tracks and trades in antiques, only it all takes place a thousand+ years in the future so the stuff he deals in hasn't even been built yet in our time...
Orion Shall Rise by Poul Anderson(and if you like it, the short story collection
Mauri and Kith details more about the Mauri Federation)
Most of H Beam Piper's work fits your request. So does Allen Steele's Nearspace novels(check wikipedia for a list)
The Mote In God's Eye- Niven/Pournelle
Santiago, A Myth of the Far Future by Mike Resnick
another SM Stirling suggestion would be
The Peshawar Lancers
One that may come close to hitting every point you mentioned is
David's Sling by Mark Steigler
and a couple of classics that fit would be
Logan's Run by William F. Nolan,
The Stainless Steel Rat by Harry Harrison, another vote for
The Moon Is A Harsh Mistress and
Starship Troopers , The
Riverworld series by Phillip Jose Farmer, and the
Nine Princes In Amber by Roger Zelazny.
There's also Dean Ing's novels, the original 3 Draka novels by Stirling(available in omnibus, I believe), the Retief books by Keith Laumer, and the Timeliner trilogy by Richard C. Meredith. Oh, and the Dorsai books by Gordon Dickinson as well as Pournelle's Falkenberg stories/novels. That should keep you busy for a few weeks.
