Cracked did a fantastic bit on how speaking with dialects can be important. Like we often say, the story is more important than getting the specific accent perfect. Little touches are also important like exactly what is the flavour of your show? Certain heavy accents can accentuate zaniness. Other times if you’re demonstrating old versus new, older characters may have thicker accents whereas younger characters would have a lighter touch.
Check out That Bad Movie Accent Makes More Sense Than You Know on youtube and consider what kind of accent or dialect best tells the story!