Instead of multiple races have lineages?

[9toes]

Ok so I have this pretty in depth homebrew ive been working on for like 2 months and i have run into an idea. I was making different kinds of elves and dwarves and humans and orcs etc., as playable races when i had the idea of instead of different races, just have a lineage that takes the form of alternate racial traits for all the races im using. You can still choose to play the standard race from the books if you so wish, but i think that ALL dwarves and ALL humans and whatnot have the exact same racial traits is boring. Humans on Earth arent even like this. They adapt to their surroundings. Eskimos are better for living in arctic conditions, whereas an Aborigine is better suited for Australia or New Guinea or wherever they live, and if you swapped the two it would be catastrophic. Bottom line is i didnt want the differences to be purely aesthetic, like how the humans are in Golarion. I wanted the choice to actually affect gameplay mechanics. Do you guys and gals think this is a good idea or just stupid?

[Rynjin]

There's a bit of that already in the form of racial trait packages (like Arctic Elf, for instance).

Seems to me that if you make more traits like that (tacked on in the case of some races, rather than as a replacement), it will work out fine.

Desert dwelling Humans get +2 to Fort saves to stave off heat related effects, forest dwelling Orcs gain a bonus to camouflaging themselves in foresty conditions, and so on.