Once you get into the larger ships, and especially once you've unlocked Jameson Memorial, I always say that if you can't afford to A-rate and armour the ship, you can't afford to fly it. Do another mining run or two and then buy it.
Properly kitted, a Type 9 is plenty capable of defending itself. Assuming you pick your fights wisely and manipulate interdiction mechanics to your benefit, you'll be A-OK. (Seeker missiles are wonderful.)
The title sentiment is apropo, but the specifics of your situation are not.