I agree that weight charts and BMI are worthless.
I'm 5'6" and 198 pounds. That sounds huge ,but for me it is on the skinny side and I don't have much bodyfat left (nor am I a bodybuilder). The last time I checked my bodyframe it was within the medium range so I guess I'm just compact. LOL
In order to get to a so-called healthy weight I would have to lose over forty pounds and that isn't happening unless I amputate a few limbs.
Realistically I am aiming to lose another 3-5 pounds. Anything more than that and I would start looking sickly. Basically I just go by how my clothes fit and how I feel.