I have already tested out most of the options for the core ships 6 months to a year ago. One of the custom shipsets I constructed has every version of every core ship made in it except Griff and Simon B types so the look was consistent and I have no shader capability on my netbook. Core ships only and everything was redone, views, positions, every niggly little problem and everything was put into balance after in the roles so it looks, plays and feels like normal except small percentage of tougher ships to fight. It feels very realistic. Also almost every ship was made as flyable by the player and I gave the ships all a good shakedown and tweaked some to make them practical to fly.
My conclusion from countless hours of playtesting:
Mambas, sidewinders and kraits make good starting hunter ships as after trade in you have lots of money for equipment and weapons. The lack of a hyperdrive(simulated at the time by script) in the mamba and sidewinder adds a different element to play. Go where the wind blows. See a wormhole, take it. Hunt the spacelane to the mainstation. Repeat. The sidewinder is a dedicated hunter, very nice dogfighter while the krait is a big target, has cargo space and can go anywhere at will. The mamba was in the middle as I adjusted it to be in line with the elite manual and gave it 10t cargo capacity. Good all round ship that mamba with some salvaging ability, harder to hit than the krait but go where the wind blows.
Adders have 5t capacity in my shipset to be able to haul people. Hard to hit an adder. Best strategy was to run and manaeuver with injectors and only fight lone ships if you have a beam laser or better and upgraded shields. As a hunter not enough shields and energy for that. Definately a good scavenger and passenger hauler and was a good challenge but not for a noob that doesn't know when to run.
Worms and transporters were also flyable. No hyperdrive. Worms were like an adder but tougher to use generally because a few stray shots and you are finished. This was when I decided that if each ship type had the possibility of upgrading the shields fully that any ship would work for the player. It would have to be figured out though if the different ships shield upgrades would have different prices and availability. As a concept an adder with shield boosters and military shield enhancement proves quite fun but maybe military shield enhancement for the adder should cost more and be much rarer to find.
Transporters were a good in system scavenger/mining vessel. As for jumping into an unknown system that would be risky using another ship's wormhole without a wormhole scanner.
I did something interesting with the ships that had some real cargo space. Minimum one passenger berth built in. It worked reasonably well so I set it up with most of the other ships. Instead of a large cargo bay option you would simply remove the passenger berths for more space. New players then have a berth to start hauling people and can rip them out when they need more space. The cobra mk3 has 3 berths and 20 t cargo space to start. Need more, rip out the berths.
I find this solution more realistic and less Dr. Who'ish as logic says you can't find more space in the same space with out removing some things. Then I added a cobra mk3 cargo 50 and cargo 70 model with an actual added on subentity external cargo bay extension, 2 different sizes and made it sluggish and slower. You know this worked quite well and was still playable and gave a medium cargo ability at the sacrifice of performance. It just felt right and I was still flying a guppy-like cobra mk3. I reasoned that the cargo bay extension was an extensive refit requiring that the ship be re-engineered or that they came from the factory like that premade with warranty which is why this upgrade is not equipment. Must be bought like that.
While I tested the vipers I found the interceptor to be quite uber and if these were available to the player they should have restrictions on legal status for owners/buyers and the owner should be at least dangerous and have to buy an expensive bounty hunter's licence.
I found the morays to be almost as good as the cobra mk3 and in my version the moray medical is a little faster than the cobra mk3 because medical ships need to go fast in emergencies. The stock moray I made a little slower and lowered the price a bit. Good ships these morays. Now if you could have some use of a ship that can operate in and on water. maybe a restriction in planetfall for ocean worlds.
The cobra mk1 was a cheap alternative to the mk3 but I found that you were better off with a Krait or Mamba or Moray actually. The trade in gives some decent kit though. Might be a good start point for the player and can go in different directions from that point.
How bout a menu choice equivalent for the difference of 150000 credits where the default ship is a cobra mk1 + cash difference.
That's my take on this from my own experiences and playtesting and shipset mods.