I don't want to start argument over voices, but I have to say that 4Kids voices were far from perfect. Especially the two voices you seem to like. James was terrible, too feminine and gay stereotyped. Not to mention the acting wasn't too good either, which surprised me, since Eric Stuart did such a great job with Brock, yet he couldn't handle James right. Ash was also too girl-sounding, not like ten years old boy. And May wasn't really much better, especially since Ash and May were too similar. With all my respect to her, Veronica Taylor did really bad job to differentiate the two voices. Not that PUSA/TPCI didn't have their own problems, especially Ash's voice was terrible and it wasn't until mid-Unova when it became hearable and bearable (pun intended) for me. And Jimmy Zoppi voicing too many main characters is not good either (but I really love the way he portrays James, after the years James got really bad treatment from 4Kids).
But to the topic, for me, the most ridiculous dub change was the constant paint-over on Ash's Hoenn Badge Case. At lest the other changes, like the rolling sandwich instead of rolling Onigiri, as ridiculous as they were, made some point in Americanizing the show (not that I like this Americanization, but yeah, whatever), but did anyone really understand the point behind removing Pokéball pattern on Badge Case?