Word does have a lot of functionalities like the one you are talking about. On the 'home' tab, there is a tool 'replacement' (I bet, I don't have the english version sorry) on the left, where you can choose the word you want to change, and it'll change it in all your document!
Plus, for the organised side, I must say Word also has quite a headstart with its 'Titles' (on 'home' tab too)...
You also have the possibility to make comments all over your stories, in case you forgot to say something and want to add it later on (in the 'references' tab).
To be honest, Word is quite an editor but sadly its main and more useful fonctions are way too unknown. Take a day to really find out how it works, and what you can do with it, it's amazing!
(P.S: no I do not own Microsoft nor have been paid for saying this, I wish though...)