Depends on the school, the classes you take, your major, other factors. There is no “T-20” uniform level of rigor. You might want to look at individual schools to see if they have a reputation for grade inflation/deflation, but nothing about placement in a ranking system is going to tell you anything about how likely you are to maintain your A. At Harvard, most people have A averages. At Reed College (ranked far lower among LACs, but mostly because they don’t play the rankings game), there is very little attention given to letter grades, but it’s difficult to get an A – and they have an excellent record of successful grad school and law school applicants. Ranking has nothing to do with any of this.
You’re a sophomore – so it’s likely that your GPA could drop a little at your current institution as you get into more advanced classes next year. Or it could rise, because you’re going to focus on classes in your major. It’s just impossible to know, but rankings will have nothing to do with it.