How could I add Optics' sight range bonus over water to Radio and Satellites as well, increasing the visible range to 3 and 4, respectively?

Look in Assets\XML\CIV4TechInfos.xml

I believe <bExtraWaterSeeFrom>1</bExtraWaterSeeFrom> is what you are looking for.

The problem is that doesn't do anything when set to 1 for Radio...