That to me sounds counterproductive. When I decide to start a civ game I usually go in knowing which civ I want to play as. So if I want to play a naval civ like Harald, I'd reroll anyways. At least starting with civs/leaders at the beginning they do have start biases which helps. I'm not sure if personas are different, but original Harald has a bias towards the coast.
Never said it was perfect, but it's a 'solution' that requires the least manipulating of the current game mechanics in regard to Leaders and graphics and map generation.
Ideally, of course, a map would be generated that gave appropriate starting positions for the Civ/Leader you are playing, but since Civ hasn't managed that in at least the last 2 versions of the basic game, I wouldn't hold my breath.
Next best, since I agree that many people want to play X Civ with Y Attributes on a Z Map, would be the ability to pick from native and general attributes to 'warp' your Civ according to the map/starting position you wind up with. That, however, would require a lot of work coming up with multiple Uniques for each Civ plus a number of 'generic' Uniques for extreme terrain situations, like Mongols on a jungle island or Canada in the desert or Norway in the exact middle of a Pangaea-like continent.
Frankly, although everyone is used to it, the current model in which a Fixed Civ and Leader attributes are supposed to magically arise regardless of the conditions of terrain, climate, biome and geographical situation makes no sense at all. You are right next to Mongols, Zulus, and Aztecs, but are determined to remain a peaceful bunch of farmers. No, you are determined to be Extinct very shortly, bcause the situation Demands different Uniques than what you were given in the fixed model that is all that Civ allows.