You say you are a fan of Factory Girl, so I don't have to sell you on how awesome it is.
Why not convert those fixtures to factories? Convert Fixtures into Factory Girl in Rails should be of assistance.
Once you have your data as factories in Factory Girl, I recommend that you take advantage of its inheritance features as shown in https://github.com/thoughtbot/factory_girl/blob/master/GETTING_STARTED.md:
You can easily create multiple factories for the same class without repeating common attributes by nesting factories:
factory :post do
title "A title"
factory :approved_post do
approved true
end
end
approved_post = FactoryGirl.create(:approved_post)
approved_post.title # => "A title"
approved_post.approved # => true
You can also assign the parent explicitly:
factory :post do
title "A title"
end
factory :approved_post, parent: :post do
approved true
end