A story where an individual, one who doesn't feel he fits in with his own people (a race that has established mental abilities), is contacted by this very alien entity and somehow the individual is convinced this is his god and he's so thrilled to go meet said god that he wants everyone else to join him along for the trip, but he needs a means of transportation, that's where our characters come in. Then later after the crew is caught up in this, it's revealed the entity isn't anything but a tricky alien that's trapped and needs a ride out of there to go whatever it feels like, whether it's Charlie Evans after his mortal body died, a bad Organian, Trelane's brother Rex who is secretly god X, Gary Mitchel after he dug out of that hole, this is what the Decker Unit turned into, or some other thing, is not a bad story idea.
Stuff that really doesn't have anything to do with that, climbing a mountain and having your ass saved by a guy wearing rockets on his feet, a "planet of peace" that's a real crap hole full of stupid asses, said stupid asses are better infantry than our crew, how they distracted the stupid asses, the ship is a piece of junk and yet another "starting over" when we started over for Star Trek 1, 2, and 5, The way the Klingon was included, as a bored ship captain without anything more interesting to shoot at.
If they wanted to involve Romulans and Klingons, then it would have been better to have them hear of the quest and try to get in on it, but that's kind of the plot to The Chase. Actually The Chase is kind of the same story but with archaeological evidence rather than a charismatic individual driving the quest. The end of that seemed like a let down, too.