I've had the same thoughts. This forum will turn you into a paranoid freak if you aren't careful. My wingspan is 1.5cm over my height, so I'm lucky there.. For me, I decided to go with a happy medium. Pick an amount where the height is noticeable, (at the very least 5cm) where your proportions aren't perfect, but aren't completely messed up.
..Or else there's always humerus lengthening. Remember you'd only need 2.5-3cm to add a total of 5-6cm to your overall wingspan.
In the end I've decided to lengthen 5-6cm.. But when I stand on books and what-not at that height, I don't feel much different. I only truly feel a difference at 8+ cm's. Makes me wonder whether it's worth it. I'm an amazing person at 5"6, and I feel 5cm really isn't that big of a deal... I don't want my femur to look out of proportion to my tibia, I don't want to have overly short arms. I just feel it's easier to ditch this whole idea haha.. To get my ideal height with proportions, I'd have to do two surgeries with a humerus lengthen. That's 3 surgeries!! Not worth it in my eyes. On the other end of the spectrum, 5-6cm just feels minuscule.
You can hide proportions easily with clothes, (minus wingspan) but I have aspirations of having the perfect beach body (I have for years) and I want to feel comfortable in minimal clothing.
Proportions vs Height is the most tormenting aspect that will play on your mind with this whole thing. But honestly, unless you want the perfect Greek bod (as I do) then your proportions will be hidden in clothing and won't be noticeable to the general public.