Between the lesbians and the religious themes, I think they just really struggled with making S American kids' TV friendly, especially in such a short amount of time. Other than Fish Eye, SuperS didn't really present them with anything problematic, thus it was a lot easier for them to adapt. (I also think they dialed back on the dated Y2K slang thankfully).
The main problem with the CWI dub was the fact it was rushed. The finalized terms, "Crystal Treasures", "Purity Chalice", and "Sovereign" were all good but they had to go through a dozen different ones before they settled.
There were also just really bizarre mistakes, like the girls wondering who owned the Mugen ID they found, even though Serena got it from Telulu in the previous episode. Or Amy saying they need to find the chalice, even though they just did an episode ago...
Thankfully, they got their act together with SuperS and everything was pretty consistent. Other than mistakenly using Rita's original name once, or renaming Melissa (which is TOTALLY understandable, since she looks so damn different), it was fairly well written. I know people like to whine about the upgraded attacks, but it wasn't any worse than the crap DIC would pull (Moon Star Power, anyone?).