Let me start by saying I do not have a problem with hunting. We are, under this civilized skin, still hunter-gatherers. Our bodies require animal food. Humans don't produce vitamin B12 which is necessary for healthy nerves and the only source of that vitamin is animal food. Hunting is how we have traditionally procured it. In my own young adult novel, the protagonists hunt; however, they hunt legally with all licenses and in designated territories, they hunt deer which is not endangered or threatened, and they eat what they hunt. I do not object to hunting if either the quarry is eaten or it constitutes an imminent threat to life or property.
But trophy hunting makes no sense to me. Why would you want to kill something just because it's big and beautiful and then drag the dead carcass home and mount it on a wall? As to the argument of "pitting man against nature", the man (and it almost always seems to be a man) is almost always armed with a weapon that is a technological marvel. If the man really wants to pit himself against nature, let him find the resources and make his own bow and arrows or spear by hand and then take on nature. That would be a much more even fight.
As for the case of Cecil the lion, personally I think this is a Casper Milquetoast dentist hypercompensating for his internally perceived lack of masculinity. The man is pitiful and probably in need of psychiatric help. A stuffed head on your wall doesn't make you a "man". For the price of his crossbow, he could have bought an incredible camera and then went to Africa and stalked all the animals he liked, brought them home and mounted their pictures on his wall to the amazement and delight rather than revulsion of his friends. His $50,000 would have been better spent on mental health treatments than big game poaching.