What kind of accent do you think Booster Gold talks with? Is it his natural one, or is it something he's developed trying to ape speech patterns of the 20th and 21st Century? I could see Booster having Skeets determine what accent would be most appealing when pitching various merchandise, then trying to adopt that to suit his purposes.
Accents don't seem to be brought up much, beyond the Claremontian style of having characters identify their ethnicity with what are I guess supposed to be phrases and exclamations of their native locales. It makes sense, with comics not typically being an audio experience, describing someone as having a Queens accent* might not do much for the audience. For example, I'm not really sure what constitutes a 'Queens accent', other than I imagine it sounds pretty dissimilar from whatever Midwestern accent I speak with**.
Back to Booster. He's from Gotham, albeit the Gotham of 500 years in the future, so I'm guessing some sort of Middle Atlantic accent, probably with traces of various other linguistic types in there (look at me, trying to talk like I know something about linguistics), to account for a blending of cultures over time***. It's not really of any importance, I was just wondering.
* What made me think of this was that JMS' Amazing Spider-Man issue with the tailor, where the tailor said he asked Spidey for help because he's a local guy, and when Spider-Man asks how the tailor knows that, the tailor responds 'Ask me again with that Queens accent how I know you're local', or something to that effect.
** I assume I speak with a Midwestern accent, excepting the moments I attempt other accents for kicks, having been in the Midwest my entire life.
*** It might be a mistake to assume that differing cultures continue blending and settlign their differences over time, but then again, this is DC rather than Marvel, so it's probably OK to bet on a promising future.