Imaginative cowardice seems like a slightly harsh way of putting this approach, but that's what it is, to me. Thinking of a concept and then completely failing to bother following through on any of its implications even slightly.
I want to call this the "Bloke in a Costume" problem: rendering a potentially powerfully imaginative choice a merely cosmetic one.
What's the antidote to the bloke in a costume problem? Being more imaginative, of course. How do you do that? Study the world and learn from it. Watch animal behaviour in particular and think about it. Empathise. Some pointers:
I was stroking a murderer, a savage. Gos knew that might had always been right, that the Vikings slew the last two kings of Northumbria because the Gokstad ship could come so strongly in from sea, that William had cavalry at Hastings as Edward III had archers on the wings at Crecy, that the press barons of the year I was writing about were right about re-armament...Hitler and Mussolini, Gos and irreclaimable villein kestrel, seals that preyed on salmon and salmon that preyed on herrings that preyed on plankton that preyed on something else: these knew that God had given a law in which only one thing was right, the energy to live by blood, and to procreate.
Unfortunate, dark and immoral goshawk: I had myself been subjected to his brutality. In the beak he was not formidable, but in the talons there was death. He would slay a rabbit in his grip, by merely crushing its skull. Once, when he thought I was going to take his food away from him, he had struck my bare fore-finger. It had been a Bank of England apprehension, a painful impotence, a Come-you-here arrest by all-powerful police - I should only have hurt myself horribly by trying to get away, and was already being hurt. He had held the glove with one talon, the bare fore-finger with the other, so tightly that only one method of escape had been open to me, and that had been to tear him in half. In the process I should have pulled all the flesh off the finger, like stripping the rubber off an insulated wire. Not from courage, but from necessity, I had stood quiet and unprotesting, speaking to him calmly until he let go.
A homicidal maniac: but now he was enjoying to be stroked.
-From The Goshawk, by TH White
What stories fail to convey is the violent greed of the mole, which scuttles along its tunnels eating the worms, bugs and grubs that fall haplessly in. There is nothing cute about a mole tunnel. It is a vast pipeline trap. And for a gentleman dressed in a velvet smoking jacket, mole is the most violent diner; he bites off the worm's head, then with his claws squeezes out any earth left in the worm, before sucking it down like spaghetti...
-From Meadowland, by John Lewis-Stempel
The life of an Adelie penguin is one of the most unchristian and successful in the world. The penguin which went in for being a true believer would never stand the ghost of a chance. Watch them go to bathe. Some fifty or sixty agitated birds are gathered upon the ice-foot, peering over the edge, telling one another how nice it will be, and what a good dinner they are going to have. But this is all swank: they are really worried by a horrid suspicion that a sea-leopard is waiting to eat the first to dive. The really noble bird, according to our theories, would say, "I will go first and if I am killed I shall at any rate have died unselfishly, sacrificing my life for my companies"; and in time all the most noble birds would be dead. What they really do is to try and persuade a companion of weaker mind to plunge: failing this, they hastily pass a conscription act and push him over. And then - bang, helter-skelter, in go all the rest.If you can create a race of goshawk-people who will willingly inflict pain and violence on somebody ten times bigger just to make a point; if you can create a race of mole-people who are very gentile, well-dressed and wise one minute and insatiably greedy assassins the next; if you can imagine the many ways which intelligent penguins would dream up to betray their acquaintances and profit from their deaths, and much more besides, then you will be a man, my son.
-From The Worst Journey in the World, by Apsley Cherry-Garrard