I did this for me, but decided I might as well share it for anyone who wants it. A kinda, sorta proper English translation.
Disclaimer: I do NOT speak, read or understand Japanese. I basically just used the machine translation Inui provided for the IncompleteEnglish setting and heavily edited it so that it makes sense and tried my best to make it sound like proper English. I did take some creative liberties with the translations here and there so it's not a 100% accurate translation, but it should be accurate enough. I also translated everything that wasn't in English, like the battle dialogue, using Google translate as the basis then editing it to proper English after.
I also altered a couple of character's names to ones that personally sounded nicer: Claude Javis was changed to Claude Jarvis, and Mr. Zetoo was changed to Mr. Zetou. If that bothers you, you can change it yourself.
To install, unzip the file, go to the HotM folder, go to the Text folder, keep a backup of the IncompleteEnglish folder in case something goes wrong, then replace the IncompleteEnglish folder with mine. Launch the game and in the Config menu select IncompleteEnglish