I use braces for foot drop and would say yes to your question of braces to keep your feet and knees in proper position. IMO I think it's worse for your whole body to have these things out if alignment, and will just keep causing more problems as other body parts have to compensate for the ones that are weak and unable to function properly.
I held off as long as possible before resorting to braces for foot drop, but now that I wear them, I am so glad to have them. Walking is so much easier with them, my gait is better, speed is better, the rest of my body is not so tired from compensating for the weakened calve muscles.
Google them and see what is available "off the shelf" I find these to be lighter and less bulky than custom made ones. I like the carbon fiber braces.