Well done for using the cargo transporter, Rotoha! Not an entirely easy proosition, but it's a good way to build up money quickly. Note that you lose money each time you trade in a ship, so it's advisable to minimise changes where possible. I wouldn't really recommend sticking with the transporter for much longer though, in case you become bored of the whole business.
If you want to stick with the culture that you know, the Freight-courier is the logical path. It's a somewhat combat-capable cargo hauler. The Arada, in comparison, is a micro warship, somewhat capable of hauling cargo. Would that suit you?
Some people buy an Arada and end their ship upgrade path right there. Certainly, it's a fine ship. I think it's better than the much more expensive Lazira, since it can carry more guns and is fast enough to avoid a lot of enemy fire.
My personal variant is the Voinian Arada; remove the phase cannon and fit three neutron cannon and a neutron turret. (The folks at Paaren won't sell you more than 3 neutron cannon, or I'd mount four in the nose.) With a warload like that, you don't need secondaries. It simplifies your logistics; add a fuel scoop, and you need never plan stopovers to resupply.
Why not copy your pilot file, then try it both ways. Buy an arada with one pilot, and a freight-courier with the other. Give both ships a whirl, and see which one you feel most comfortable in.
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