Really? I can't say as I disliked any of the dubbing for 'My Bride is a Mermaid' or 'Ouran High School Host Club', even if I don't know the VA's well enough to know which characters they did. Of course, I don't pay that much attention to the credits, so I don't have much in the way of most/least favorite VA's.
I don't know if the English dubbing for The Slayers (the first season) that Funimation has is the original ADV English dubs or their own, but I will say that whoever they had doing Lina Inverse in that was horrid. There aren't that many animes where I have a strong impression per say, other than that the longer ago it was dubbed generally the less I like the dubbing (it took years before they finally managed to find American VA's who could do the roles and not be an insult to the Japanese VA's who did the original dubs). There are a few miscellaneous exceptions of course, but for the most part the majority of the English dubs I like were done within the past 5 to 7 years, with gradually less frequent exceptions before that. Then again, until the American otakus who watched the animes started raising a fuss about having English dubs that were as well done as the Japanese dubs the companies didn't have much of a reason to find good VA's.
There is one normal actor who has done some VA work, but that was years ago, that it's too bad he might be too old to do even VA work, as he did an incredible job in the little bit he did, but then again how much would we need his distinctive British accent for most animes?