A couple of quibbles/points of discussion:
First, despite the fact that we saw a glimpse of an extraordinarily passive, pacific society does not mean that the Ocampa are all of a piece. They will have scoundrels. rogues, and villains just like any other society- particularly once the Caretaker "abandons" them and real desperation begins to set it.
Imagine the fun if one such Ocampa actually joins your Kazon group for his own reasons...
You have the potential for infighting, political drama, and the ultimate questions "Who is manipulating who?"
"Are we advancing the Kazon Oglas's interests, or those of Ocampa X?"
Just because the players aren't allowed intraparty in-fighting doesn't mean you're not.
Second, the Ocampa homeworld is extraordinarily dead, dry, and barren. This is both boon and bane.
On the plus side, the lack of nucleogenic particles precludes rain- which means it prevents the formation of any other form of condensation as well. No moisture means no rust, mold, mildew, or "wet" rot.
These conditions will serve to preserve pretty much any non-organic materials- including the ancient technologies.
The greatest threat to such troves will (as you have already deduced) be raiders and looters- which means only that your party will need to go deeper, into the darker, more dangerous, more obscure locations to get what they need.
On the minus side, the planet is a massive, empty sandbox of death. After a thousand years with no water, no rain, no life- there's going to be almost zero native opposition and very little chance for conflict or drama. As the Narrator, you're essentially going to have to either create conflict in your party or import it from off-world.
In the meantime, the Ocampa will not (cannot) be idle. With the exception of their energy needs, the Ocampa live in a closed system. They have everything they need on hand except power. What would they trade to get it?
If there's anything their world is good for, however, it is solar energy. If they were to park a sufficiently large solar plant above their city, it would help- but not solve- a lot of their problems.
Of course, they'd need a security/maintenance force to protect such an installation from the elements and other raiders...
Playing your cards right, this could be anything from an equitable arrangement to a repeat of Bartertown from Thunderdome.
One possible solution to this is the fact that the rest of the sector is really no better off than Ocampa (the world).
The Talaxians have a star-faring culture, but Neelix was still amazed at all the water Voyager possessed. This suggests that the Kazon/Talaxian technology levels are pretty much par for the course.
If word were to spread that the Ocampa had begun reclaiming their ancient knowledge/technology and were willing to share/barter/trade for either supplies or advanced knowledge, their world would quickly become a magnet for treasure seekers, information brokers, applicants, supplicants, and profiteers of every sort.
The Trabe will be keenly interested in such a development for three reasons:
1) they would see any effort to arm/equip/unite the Kazon as a threat to themselves and will fear the altered balance of power a Kazon/Ocampa alliance would represent.
2) they will likely covet any recovered knowledge and technology for themselves,
3) they will see the Ocampa as rivals for power and control of the sector.
As such- and given their penchant for violence, treachery, and deceitful conduct, the Trabe have the potential to become the primary villains in your campaign.
The other two problems you're going to face are cultural and thematic.
Culturally, the Kazon are scavengers, not builders and warriors, not scholars.
Basic literacy will be a problem for all but a select few and you can forget any sort of advance theory. The onscreen evidence suggests that technical skills are passed down teacher-to-student in an apprenticeship-like arrangement. What training there is is going to be focused on practical applications, not the underlying theoretical principles.
This makes it all the more likely that your party will either begin with skill set necessary to operate a ship (which begs questions about not only where and how they got the knowledge, but why they were abandoned on the surface) or must acquire those skills.
If it's the latter, a "friendly" Ocampa teacher becomes that much more essential to the story line.
The thematic problem is more of a personal prejudice than a serious problem: take everything the follows with a grain of salt.
It's your group, your game. Do what feels best to you.
To me, the appeal of Star Trek is the "hopeful future" that Roddenberry created and others expanded upon. Even DS9- with its war-time theme, clung to the idea that humanity and human values have a bright future. Star Trek is as much about exploring the nobility of the human spirit as visiting strange, new worlds.
I am concerned that you will have a hard time both engendering and maintaining that same sort of atmosphere in your campaign- and that the hope will be lost in the pursuit of new technologies and new acquisitions.
Playing "barbarians in space" is all well and good, but it's not "Star Trek".
My concern is that you may wind up playing in the Star Trek setting rather than playing Star Trek.
If that is your desire (and the desire of your players), more's the better- but the dichotomy should (at least) be taken into consideration in your planning.
Here are some quick mission ideas, I came up with. Use them, discard them, burn them in effigy, if that's what makes you happy :
- Power couplers in the Ocampa city are beginning to fail. The Ocampa hire the heroes to escort an engineering party to the ruins of an ancient Ocampan city to scavenge more. Automated defense systems or another scavenger party stand in their way.
- In an effort to reseed their world with nucleogenic particles, the Ocampa hit upon the brilliant scheme of altering the course of cometary ice to impact with remote sections of the planet's surface. In order to accomplish this, they hire the heroes to help resurrect an ancient Ocampan deep-space tug. Once the ship is space-worthy, the heroes have to locate and redirect one of the cometary bodies. The bad news is someone that has done their sums wrong and the cometary impact will cause tremendous damage to the Ocampan city. The heroes need to correct the trajector now, quick, and in a hurry. Will outsiders interfere with the project? If so, why?
- Long range sensors indicate an instrument pallet (a probe) using a tetryon reactor is nearing the last position of the caretaker's array before it was destroyed. The array itself was powered by tetryon reactors- is the probe itself Caretaker technology? What secrets might it hold?
- The Ocampa have uncovered records which make vague references to a vast, forgotten archive buried in the ruins of an ancient city half-way across the planet. They hire the heroes to travel to the library (either on their own or escort a party of scholars there). Although the archives are intact, the surrounding structure is in extreme danger of collapsing- possibly trapping the party.
- Traders appear offering to sell advanced technology- some of it Caretaker, some of it Federation in origin. Something is wrong... Are their wares genuine? Where did they acquire it? What are their real motives?
- (False) rumors surface of an ancient Ocampa super-weapon buried in the northern deserts. The weapon is said to have the potential to reshape the face of the quadrant. The heroes, the Ocampa, various other Kazons sects, Talaxian dissidents, and the Trabe are now in a cut-throat, winner-takes-all race to find seize, and control the weapon of the century.