I'd say Dil, based not on whether or not I like her more than the others, but based on realism. She's an ancient alligator/crocodile (not sure which exactly). They have tough hides, so it's unlikely that Strut or Ozzy would be able to do any real damage to her. And Ichy..well, he's a bird, lightweight and more fragile than the others. His main advantage is that he can fly, but he still wouldn't stand much of a chance against Dil. He wouldn't even be able to scratch her.
Of course, this is not to say Dil wouldn't have weaknesses. She's almost blind, so she would have a hard time telling where her prey was. Of course, if she has a good sense of smell, she could use that sense instead to find her prey. She's also rather slow. Crocs and gators aren't exactly known for their constant speed. So she would benefit from ambush tactics.
The main reason I voted for her is because of her sheer size and power. Even if she can't keep up with the others, there isn't really much they could do to really harm her. I don't Ozzy and Strut are strong enough to push a boulder on her that's heavy enough to kill her. And I don't think there's anything Ichy could do without getting outside help. And forget about trying to bite or slash her. Oh sure, it might might hurt her (Ichy's bite did hurt her I think) but it wouldn't do any real damage.
Dil, however, would easily be able to crush their bones with her jaws and cause a lot of damage with her tail. She's also more compact than the others, lower to the ground and on all fours. This means she'd be harder to knock down and her vulnerable underside is more easily protected.
