Herms translations are more accurate. He is straight translating from the JP manga, meaning it is as literal as it can get. Some lines will suffer some twist (even if minimal) from TOEI maybe when being used into the anime, which isn't the same with out friend Herms. For instance, the JP anime has Piccolo saying he is sure he will take the androids down, whereas Herms has Piccolo saying he doesn't lack confidence (whithout even specifying his own powers). Which would you go by?
But this sounds fun, I am all for helping in this project. I think it'd be easier to organize if from saga by saga. For example:
Raditz saga:
<All the strength quotes>
Vegeta Saga
<All the strength quotes>
It'd be easy for someone who wants to help as they can just watch the episode in sequence, rather than finding all quotes related to Goku who might be both in chapter one and in chapter 291.
As for an online version, here's one:
http://kissanime.ru/Anime/Dragon-Ball-Z
Those are the original subtitles.