Nonsense!Fleet carrier shouldnt be referance point for game progress, also you didnt included in your calculations that you are losing only 10% of value of your vette hull if you decide to sell it, so actully with 1! session you made up for your corvette purchese, i wouldsay it's very generous payouts, even if you play less than 2h per day, i remind you, it's impossible to lose fully engineered ship to npc's
It is quite possible to lose a fully engineered ship to NPCs, admittedly you have to be being greedy and inattentive at the time and of course remember that fully engineered does not mean the ship has an optimal build.