It's almost comical how many people seem threatened/offended by the addition of a bird mascot. Mascots aren't generally for the hardcore sports fans, they're more for kids or people who don't care as much about the game they're at. They're good for public appearances and events. They're an icon at events that kids can recognize and get excited about. Do you think that many young children are going to remember individual players at sporting events? No. They remember goofy mascots dancing in the stands or down on the court/field like Fredbird, Louie (Blues), Clark (Cubs), etc. I think a mascot would be good for events, some schools send their mascots to local children's hospitals to brighten the day of kids there, players doing that is cool, but the kids aren't going to recognize them generally. I loved Chief growing up, I was heartbroken to see him go, but in today's climate, I get it and I think it was appropriate. Chief isn't coming back and it's time everyone accept that and the "Chief or nothing" attitude needs to die. The Iowa State Cyclones have a Cardinal mascot because their colors are cardinal red and gold. The Miami Hurricanes have an ibis as a mascot because "it's the last sign of wildlife to take shelter before a hurricane" and "the first to reappear, a sign that skies are clearing" (from Univ. of Miami website). We can keep the Fighting Illini name and move on with a mascot that differs from that.
I think the Kingfisher mascot is appropriate. Native to Illinois and the females (males don't have the orange from what I've read) share the orange and blue color of the university. The Alma Otter thing was cute, but I feel like there's less of an Illinois connection. Hopefully, if it's passed, the school can hire a professional artist to design something a little more "fierce-looking" than the student's design, but it's a process.