I watched Enemy: Starfleet from Phase II productions for the second time this weekend. Basically, its about a hostile alien race that manages to appropriate a missing Constitution-class ship, the USS Eagle. Interestingly, its Captain was an Andorian (played in this film by Vic Mignona). Out of curiosity, I went to read Memory Beta`s info on the Eagle: http://memory-beta.wikia.com/wiki/USS_Eagle_(NCC-956) which revealed the Eagle as once being an all-Andorian crewed ship, much like the USS Intrepid with its all-Vulcan crew. Now, I don't really personally care for the Tellarites as a race (my exposure to them is basically The JOURNEY to BABEL, with a couple cameos in TOS). But as a Federation founding race, don't they also rate their own starship?
Tellarites rule. I never understood the no-love they've gotten over the years. People getting excited about maybe seeing an Andorian in TNG... nuthin for Tellarites. Big excitement when Andorians showed up in ENT... nuthin for Tellarites. When they finally DID show up in ENT... *still* nuthin. No big excitement and anticipation like for the blueskins. Everyone seems to want the Andorians, but Tellarites get no respect. What, cuz they're pigmen?? And I really liked ENT's new take on the makeup design, swell new pigmen. Tellarites rule.
Tellarites have always been one of my favorite Trek races. The reason why they never appear in TNG, DS9 or VOY is because Rick Berman didn't like them. In fact, the main reason why is because he thought the make-up for them was stupid-looking. Coming from a guy who thought that just slapping something on someone's forehead was the height of make-up design originality, that doesn't surprise me. It's the same reason why Andorians don't appear all that often, and when they do they're only either in the background or on-screen for a few seconds. Berman thought that aliens with antennas were to "50s B-moive" alienish. In fact, when ENT came around, he had to be convinced to use Andorians or Tellarites at all. Others were able to convince him that make-up techniques had advanced to the point that they wouldn't look "silly." Personally, I still don't think that explains why Tellarites STILL appeared so little on ENT. They definitely got no love and I don't know why.
IF you asked me, I think Rick Berman just didn't know how create convincing characters very well. That's why they probably were afraid of the rating dropping. Look at DS9... Everybody loves DS9. I ask people which ST they prefer...most of them would say DS9. I love the characters were developed; it had depths and life. To bad they didn't listen to Ron Moore and Ira Behr. Well that's in the past now. I guess they all made up. Everybody made mistake...no one is perfect, right?
IIRC, and I followed this fairly closely, Berman never commented on Tellarites. Way back after "Journey to Babel", it was Fred Phillips who was never happy enough with his work on the Tellarites. He tried for something unusual with the deepset eyes, but the actors could hardly see, and that's why John Wheeler holds his head at a weird angle in the episode. Fred then modified the makeup appliances for "Whom Gods Destroy", and again for "The Lights of Zetar". When it came time to develop aliens for ST:TMP, Fred created all-new aliens, but the Vulcans were back, of course, and newly-antennaed Andorians, using new, no-bake, "slip latex" techniques. The Andorians returned "because they were Fred's favorites", according to Roddenberry in interviews. Instead of revisiting Tellarites, Fred developed the Kazarites, who were more simian than porcine. Curiously, the two Tellarites featured in ST IV are wearing ambassadorial robes originally created for TMP's Kazarites. Stock outdoor footage of distant aliens in Tellerite/Kazarite robes (from ST IV) was reused in several TNG episodes. Yep. "Hokey" was his term. And he remained unconvinced of Andorians being believable in speaking parts until miniaturization of the electrical parts, needed to puppeteer their antennae remotely, became possible and cost-effective. So? He was right, pretty much. No one pitched Tellarite stories? Westmore was busy designing his own aliens? You may as well ask why no TMP, ST III, ST IV, ST V or ST VI aliens appeared in TNG, DS9, VOY or ENT. Tellarites were painted as feisty, argumentative, one-note characters in TOS. Writers tended to created their own aliens, or enjoyed developing others. Berman didn't really create any aliens. Westmore did. Berman only had to sign off on the designs he thought would work well, or the designs that fitted descriptions in writers' scripts. In any case, Rick Berman was following a Roddenberry suggestion from the first TNG writers'bible: that space was really, really big, and that TNG should forge ahead into new territories, not have the Enterprise buzzing around in the small neighbourhood featured during TOS. So... few Vulcans, no Andorians, no Tellarites. By not using Tellarites? Get real. The ratings dropped because ST wasn't appealing to as many members of the general public as TNG did in its first run, and TOS in syndication repeats.
Have a look at the book series. Star Trek's "S.C.E." (Corps of Engineers) has a continued Tellarite presence. Tev won't show up until about a third of the way in, though, when he comes in as second officer of the da Vinci. Good stories and as I recall, Tev is quite obnoxious - at least in the beginning.