If I use make_class and I pass an OrderedDict of name/attribs, the created class does not have these created in the original order.

Somehow make_class ends up using some plain dicts for attrs (whether this is originally a list or an Ordered mapping) and my attributes order is lost... which means that down the road my serialization order is also lost and that eventually the order of the arguments is not entirely clear.
As it is this creates classes with a pseudo-random attributes order (as it depends on the Python hash function used in the dict)