Looking at your list, Masterpiece figures with a hint of third party are going to be your best bet.
Autobots:
*Optimus Prime - MP10, no contest. You can either go for the Takara release, or the Hasbro release. There's really no difference between the two, other than some minor deco differences.
*Hot Rod/Rodimus Prime - MP09, but if you just want Hot Rod, the
Classics Deluxe "Rodimus" was released several times as the character.
*Ultra Magnus - Either Keith's Fantasy Club (KFC)'s "Citizen Stack", or you can wait for the upcoming MP22 from Takara.
*Springer - You could have a whack at Fansproject's Warbot Defender, but the
Generations Voyager is infinitely better. Defender if you want as close to
Generation One-accuracy, but for playability and posing, the
Generations Voyager.
*Arcee - Even though we haven't seen her yet, I suggest waiting to see how the
Generations Deluxe will turn out. If you're impatient, you might want to go for Perfect Effect's "RC Motorbot".
*Kup -
Generations is the only one I feel is the best one to pose. If you don't like it, then you're stuck with the original
Generation One figure.
*Wheelie - I think X-Transbots is making an MP-sized Wheelie, dubbed "Ollie". There's the official
Universe (2008) Legends figure, which is adorable in its own right. Then you have
Generations GDO Wheelie, a retool of
Reveal the Shields Jazz.
*Blurr - There's the
Generations Deluxe, a retool of Drift. I heard there's a third party company working on a more
Generation One-inspired Blurr, but I forget who it was. Maketoys? Mastermind Creations? I can't remember.
*Blaster - Unique Toys "Soundmixer", but if you're cheap like me, the recent
Generations: Fall of Cybertron Soundwave retool is a good alternative.
*Perceptor - Once again, if you're wanting to be cheap,
Reveal the Shield released Perceptor as a Deluxe. KFC also has an offering that is probably what you're more into, with their release of "Mugan Scope".
*Grimlock - MP08
*Dinobots - FansToys is making a Dinobot themed line, starting with their release of "Scoria", and working their way up to include, oddly, Grimlock.
*Jazz -
Reveal the Shield released a Deluxe "Special Ops" Jazz which is pretty neat.
*Cliffjumper - The
Classics Deluxe redeco of Bumblebee is pretty good.
*Bumblebee - the aforementioned
Classics Deluxe, or you can wait for the Masterpiece figure.
*Ironhide - either the
Universe (2008) Deluxe, or iGear "Weapon Specialist".
*Brawn - There's a Legends figure in the
Universe (2008), and there's iGear's "Hench".
Now for my favorites, the Decepticons.
*Megatron - Masterpiece, but it's oversized compared to the current Masterpiece figures, it's super fiddly, super thin, prone to breakage, it goes on and on. I wouldn't recommend it. There's also ToyWorld's Hegemon, but I hear it's rare.
*Galvatron -
Universe (2008) released a Deluxe, but it leaves one wanting. I recommend Unique Toys's offering, "Mania King".
*Starscream/Seekers - MP03 for a great jet mode, but MP11 for robot mode. Not to say MP11's jet mode is bad, but it's been modified slightly to accomodate for the better robot mode that MP03 lacked. So far, only Starscream, Thundercracker, Acid Storm, and Sunstorm have been given the MP11 treatment, but the only Skywarp out now is based on the MP03 version. You can go for the MP03 Seekers, but their robot modes are flawed (obnoxious hip kibble designed to look like katana scabbards, weak plastic around the joints that flip the wings up for robot mode, doesn't stand well at all, etc.).
*Soundwave - MP13. However, there's also a configuration that you could do to the
Generations Voyager.
*Devastator - For cheapness, the
Classics Wal*Mart exclusive redeco of the
Energon Construction team/Constructicon Maximus. If money's not an issue, TFC Toys's "Hercules" is a superb guy.
*Shockwave - FansToys's "Quake" is as close to a Masterpiece Shockwave as possible.
*Astrotrain - The
Classics Deluxe is as close as anyone's gotten. Takara released this figure in their
Henkei line in a cartoon-accuate deco.
Miscellaneous:
*Unicron - Japan released a retool of
Armada Unicron with a more
Generation One-inspired head. What it's called, I don't remember.
Here's what it looks like, if you're curious.
*Sharkticons - Unique Toys's "Sharkies" three-pack is by far the best version of the Sharkticons to date. There's a rumor that one of the rumored upcoming
Generations Legends figures are to come with Gnaw, who is traditionally a Sharkticon.
*Wreck Gar - There was a Deluxe released in
Reveal the Shield, and the cool thing about this figure is that if you have more of this specific mold (say, for instance,
Generations Junkheap), there are a couple tabs on his groin that clip onto the other figure's bike mode's seat that lets you have him ride the other figure's bike mode!
Be aware that all of this is a buttload of money you're talking about. The entirety of this list probably goes over three or four grand, at least.
Also, you were in the Navy? Far out! I'm a cadet PO1 in my school's NJROTC unit, and I aspire to enlist as a Marine after I graduate this June. What was your MOS, out of curiosity?