Absolutely. Some people are one and done with their flagship, which is often very reasonable and always very enviable!
Of course maybe you also would prefer a different format of college, or would like to go some distance from home from college, or would like to be in a certain job market for experience opportunities, and so on. In cases like that, exploring schools that would fit those criteria and be affordable might be reasonable even if they are not “better” than Illinois, just different.
But none of that is mandatory, just something to consider.