A nice voice. In terms of accent, if at all possible, Irish (as long as he doesn't sound like the late Dr Ian Paisley) or next best, Scottish (as long as he doesn't sound like Rab C Nesbitt - or look like him
), but BBC English will do fine. Soft Geordie is good too, or occasionally Yorkshire (Clive, the dad in the Yorkshire Farm series is rather attractive
). Even a touch of Scouse.
Really, really don't like London regional accents or Birmingham.
Sorry, Aussie, American or South African don't do it for me!