Reducing executable size in shipping

I’m interesting in hearing ways in which I can reduce the generated executable size for shipping builds. Currently a shipping build produces an approx. 45mb executable and an approx. 500kb game dll. Short of manually disabling code I don’t want / use, are there built in compiler flags I can pass to UBT that will turn off engine features I don’t use? If there are, how fine grained can I get with these options? Are there plans in the future to make it easier to tweak these settings?

Thanks.