I think most people use wild words or anime ace, but I've seen others. A bunch more are listed here as well. I personally like using wild words for regular text and a combination of yellowjacket, comixheavy and destroy earth for sfx, but this will definitely change depending on what kind of manga you're typesetting also.
I liked openoffice a lot, but it just doesn't hold a candle to its libreoffice fork anymore. You could try that as an alternative. Maybe it will help with your workflow? But in the end a word processor is just a word processor, right??
Good job with the translation and thank you for picking this little gem.
I can ask around for nicer fonts and help you out with QC and some cleaning, if needed. I personally haven't done much scanlation work, myself, but I'm willing to help you out with anything. I really appreciate you for picking up and carrying the torch and would love to see you continue working on this series.