Hell, the whole HSA catalog probably falls into mild-medium. Personally, the SCdlH Principe was probably the one that first made me think "ok, I need to try more". Most Cubans really need some down time after shipment, and you'll likely need to lower your humidity drastically if you are following 70/70 rules. Cuban quality control can be a bit iffy too, so not all of them will be winners, but I've not run into a entirely bad box yet (though I know others have reported such experiences).
In addition to the above Principe, I'd say try Hoyo Epicure no. 2 as a good introduction. The RyJ corinito En Cedro is also a great little inexpensive stick.