Interesting that you bring up coyotes being bigger, I read an article several years ago that said the wolf was not really eradicated in most of the US, it had crossed with coyotes and created a hybrid that was different from the traditional coyote or wolf. According the the article the coyotes they did DNA samples of had wolf DNA.
The man that did the research for the article got curious as to why there were few to no natural wolve populations, yet many coyotes when man had tried to eradicate both. He wondered how the coyote survived and the wolf did not. He came to the conclusion that todays coyotes are a hybrid of yesterdays wolf/coyote crossbreeding.
One problem is that the wolves they are re-introducing are not native to the lower 48 states, hence that's why they call them Canadian wolves. The native wolves from 100+ years ago ran in the range of 40-50#, not the 150+ that is roaming our western states and moving east and south.
There was an article in Western Horseman magazine a year or two ago about a man and his wife riding in Idaho and a pack of wolves was circling their camp one night. The next day a wolf started for the wife and the husband, carrying a rifle, dropped it when it was within 10 feet of his wife.
The family and I are heading for the mountains of Wyoming with our horses in a few weeks and I'll be carry a rifle and a sidearm. The wolves and cats are getting bolder all the time. No sense taking any chances.