<p>A 2100 is fine! Definitely not mediocre. Is that your superscore or best single-sitting? Don’t second guess yourself. That score is well within the middle 50% regardless, and if your essays, recs, and ECs are good your chances are just as good as most others here on CC.</p>
<p>For me, my ACT and SAT scores were always comparable, and I’m pretty bad at vocab too. 
But you never know!</p>