the Dialect Debacle

With everything that goes into writing a novel, you'd be surprised at what is nearly universally depicted as the hardest part—with the exception, of course, of having the courage to actually sit down and stick to it.
You'd think it would be research, trying to figure out obscure facts like how Vikings cooked pancakes or what their hair looked like. Or maybe character development. After all, it's not every day one creates a multifaceted person out of thin air. Or is it deciding how they look, or what they sound like, or where they live?
Nope.
It's writing out their accents.
I got pretty slammed recently by Irish people berating the “Lucky Charms” accent I used while writing Where the Clouds Catch Fire. Ye know what I'm speaking of, the wee accent that's used by all on St. Patty's Day, nivver mind how right it is. Och, an' the Scottish accent's worse, as ye're tryin' to describe a brogue wi' apostrophes an' contractions. Never mind the Norse accent—it's simply a crisper version o' “Normal English” with a few apostrophes fir desired effect.
I wonder how many countries I offended in the above paragraph?
Of course, I didn't mean any offense. I'm a Texan. I've never been to Pennsylvania, much less the British Isles or Norway. And all the YouTube “tutorials” about how to speak with Irish or Scottish accents are complete rubbish. Most people don't even know there's a difference between the two. I didn't.
It's sentence structure and the like that the best accents use. Aye, and there are a few misspelled words here and there, but you needn't use too many. Even the Queen's court don't speak perfect English. You needn't bother spelling out everything, or faith, it gets too confusing.
Coupled with sentences like “Her Scottish brogue was as thick as a plaid blanket” or “He replied with a crisp Norse accent,” this words splendidly well. It's easier to follow and, in all actuality, more realistic. But it does mean one thing for me.
I'm going to have to go back through all 156 pages of Where the Clouds Catch Fire and fix all the dialect now. Or I might decide it's too much work and my primarily-American audience doesn't give a crap. I'm not sure yet.
What's your suggestion? Should I take a deep breath and make my book better, or stick with the Lucky Charms accent? Let me know in the comments below. God bless you, dear reader, and have a wonderful day!