This has been hashed out probably 1000 times on this site. We have talked it up and down, we have bashed, we have praised and we have argued about Sam. But, speaking from experience of being Sam back in the day, I can say this. There is nothing wrong with the character, there is nothing wrong with the concept of Sam. I do think it would be better to have him be just one specific animal like a fox or a squirrel, but that is conjecture.
What the real problem is, is that we are the Sycamores. I love being the Sycamores, I absolutely love the uniqueness of it, I love that we are the only school in the world with an actual tree for a mascot (yes Stanford uses a tree symbolically, but they are the Cardinal). But, inherently, the use of a Sycamore tree as a mascot leaves little room for options. Sure we could have a bird or another animal that lives in a tree, sure we could have a big tree running around, and a million other ideas. But, the truth is that none of those will work and have been tried in the past. We had a huge leaf costume, we had a tree for about a year (I am told). Why do you think that in the 60's the university created (out of thin air) Chief Quabachi and the Princess? Because the Sycamore just doesn't lend itself to many options. But of course, and rightfully so, in 1989 the University did away with the Chief. So we had to have something, ISU knew that the tree costume didn't work and that the leaf was a bad idea. So they came up with Sam. And Sam is a fair and good representation of ISU.
As Bally said, it is about the person in the costume. And trust me it is a tough job. It is not easy and takes a special and gifted person to be able to excite the crowd, to get the students going, etc. Mascots in the NBA are paid big bucks because it is such a difficult job. Look at one of the BEST mascots in all of College, Red at Western Kentucky, he is a red blob that looks like Grimmus from McDonalds...but the guy in the costume makes him AWESOME!
So, I appreciate your initial post, but I think that, in this case, Sam isn't going anywhere at all. He is here to stay. Now, the real question becomes why, out of 13,000 students (roughly) where and how is a replacement found? Can ISU foot the bill to send this person (or 2) to mascot training at the national cheerleading camps? Etc.