The "haitch" thing isn't a regional thing, it's origins are based in religious differences. It still annoys the heck out of me, and puts me off watching an H2O mop demo on QVC.
In the English-speaking world the Northern vowels prevail, with many non-English speaking students learning American pronuciation rather than that of Southern English/Australian longer vowels.
I like regional accents but for a person appearing on telly they should at least speak with inteligance, correct grammar and use of vocab which isn't the preserve of any particular region.
As a Lancashire lass living down South I've insisted on my children pronouncing their consonants (I'm less bothered about their vowels). Whereas their peers may, for example pronounce "Mill Wall" as "Miw Maw" and "South" as "Sowf", I wanted them to have clear diction. Equally I don't want to hear them say "ain't" or "don't" where they mean "isn't" or "doesn't", or "them" instead of "these". All the regional words still used in the northern counties of England have strong links with Anglo-Saxon words which add to the richness of the English language and I loved the fact that relatives of my grandparents generation in Yorkshire still used the singular of "you" and "yours", saying "thee" and "thine" which today sounds archaic to my kids, but then I hear their contemporaries saying "yous" as a misguided plural of "You" but not because they have heard it in Celtic-originating regional usage (common to Scotland, Ireland, Canada, Merseyside, Australia). Maybe they yearn for a distinction between "you" singular and "you" plural which we've lost?
I don't mind my kid's speaking in their current vernacular as long as they don't write in it and understand the difference. I am a language snob and I'm not ashamed to admit it, but how dull it would be if regional richness is watered down.
Meanwhile, back on QVC I don't mind Ann Dawson's strident voice and quite like Craig's soft Bristolian delivery; it's usually the content or the tone of voice which makes me switch off not the accent.