Get yourself an adder then. It can do everything the hauler can do and it can defend itself. Only about 80k credits so it's pretty cheap
No No No! lol!
I went that route and regretted it! I owned an Adder before I finally found a Cobra MK III, and after getting a Cobra all decked out, I thought it made sense to buy another Adder and turn her into a well equipped miner/explorer. WRONG! I just couldn't get the ship configured the way I wanted, and having ONE LESS MODULE SLOT was really a deal breaker.
So what did I do instead? I bought a 2ND COBRA MK III!
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While this didn't seem to make sense at the time I bought the Adder, now after loading out the second ship with all the mining and exploration specific modules and gear, PLUS the additional module slot, I think this really is THE WAY TO GO!
I know there are other ships out there that put the little ol Cobra MK III to shame, but I would need enough credits to literally buy a fleet of Cobras to afford ONE of those bigger ships. Now having spent enough time with many of the smaller vessels, I really do feel that the Cobra is the best overall ship to own at my rank and levels.
Having two of them with each built for a specific type of mission, I can do my various activities far more efficiently, and the cockpit is always that nice familiar layout and great visibility that I LOVE about the Cobra's cabin design.