I actually don't mind that it's run this long, though I do look forward to the ending. The childhood friends are alright I guess, and are by far the easiest way for Gosho Aoyama to make two people fall in love.
However, I really would love to see Shinichi be beaten by some detective other than his dad.
Although that may seem a little odd, I don't mind the timeline much. If the characters honestly aged at the same rate as us, DC would've been finished years ago.
Meh, I think it has plenty of romance. It was never exactly meant to be under the romance genre (though of course it must be included to attract more readers and to make it a little more realistic).
I think DC lacks a little in BO arcs and is taking a little too long with some of the underlying arcs (Bourbon), but overall, it doesn't seem too bad to me.