There is absolutely nothing that can be done about new voice actors, but as long our characters sound the same, that's all that matters to me. The main characters are consistent throughout the series with their voices, but Littlefoot sounds like a girl in 13, which is unforgivable.
For me, I liked Mr. Thicknose's original voice better! I mean, he went from an old man to a ..a...a person with the deeper voice! D: I dunno. I just feel it harmed the character (MINORLY, though).
I'll always think of Eli Vance from half life 2 whenever I see Mr.Thicknose. Always.