A few images:
1.) Here's the plasma in the bussard collectors from a "Ships of the Line" calander a few years back:
2.) The "phaser turret" or "ion pod" on the big TOS Enterprise model:
3.) and on the MR TOS Enterprise:
1.) I never cared for the non-vane look on TOS E myself. Fine for NX-01, but never saw the point of just knocking the vanes off TOS E.
2. and 3.) Oooooooooh, the (infamous) E nipple you mean. In my opinion that was never a turret per say, and I never remember Jefferies or TGBOTG ever referring to it on drawings or in words as being such. I could be incorrect of course, but there is nary a "making of..." Star Trek book that I have not read cover-to-cover.
On the older shots, I just feel some folks think they see something there (that isn't really), and that may have spawned the idea of it, which given your later pics, the idea seems to have proliferated into some of the newer incarnations and/or interpretations.
I have sO many shots of the original filming model, old and with the whore's make-up/paint-job she now has to suffer with at the Smithsonian, and there is nothing that comes close to the definitiveness of your later shots, where it was actually built on as part of E.
Of course on TOS-R they still didn't use the ion pod as the phaser turret:
Here's a link to a very high resolution image of TOS-R Enterprise that shows the ion pod: http://www.trekmovie.com/images/newent1.jpg
Man, finally seeing it up close (thanks for that link) the TOS-R E is not a very good model IMO. It's OK, but man it lacks IMO. And it's adding detail and theory that contradicts (IMO) the industrial working design layout of E. And more illogical (big pet-peeve of mine with models) concepts on E. There's not even any emitters where their beams are coming out. They just repeated TOS' fudging, but in the 21st century now. Tsk tsk. Remastered? Re-bastard more like it, LOL.

And they almost did it! Sona mobile or some such was about to. That never happened though. So when the iPhone came out, I just figured someone would make a case that would be TOS-o-riffic.
Still keepin' the dream alive.

If you're considering blue as the main color for your nacelles, might I suggest some orange accents either around the edges or in the center as an accent color? Perhaps blue as the overall color of the 'plasma' with orange being some sort of reaction taking place. Since the main color of the original nacelles was orange it makes sense from an 'evolutionary' point of view and the colors just look good together in general anyways.
Well Venardhi, good points, thanks for sharin' 'em.

However, I feel using too much multi-color will only land me back at, or too close to anyway, to the TOS original Christmas-tree efx. I am trying to extrapolate a progression sure, and I think with the blue/white/hints of aqua it falls nicely in-line with the dominate saturated blues of the nacelles in TMP refit. My blue will be less saturated though, falling in-line with the softer less saturated peach color of the original TOS bussard effects. Going too saturated IMO, they start to look almost cartoonish to me now (case-in-point, why I don't like my first red bussard efx). Saturated red worked back in the day, but not so much for me these days.
However, I have worked out to have some slight reddish tones (de-saturated as well) showing up on the metal of the vanes themselves, adding a touch of color variation. I feel the warm tones do well to imply perhaps some heat being generated from the plasma churning, then onto and showing up on the metal vanes. Again, not red-hot, just very subtle, and just enough to keep the blue from taking over completely, and thus becoming too mono-tone, which, IMO, equals visually boring. My first rejected blue bussards test shows this idea of one color being too dominant, and too saturated as well (thus a bit cartoonish IMO).
I am a firm believer in the "less-is-more" approach when trying to obtain conceptually realistic results. There is always a logic behind all that I do. So rest assured at least, that nothing is ever just thrown in without any thought behind it first.
Thanks for you thoughts and Trek-Talk guys. Again, I really appreciate you taking the time to share them with me.

LLP,
deg