Word Order in typology

 There are a linguistic universals along the lines of: "If the dominant
order is SOV then..." and so on. But for a lot of languages the ordering
NPs is mainly determined by factors other than their grammatical role.
For instance, a lot of languages vary word order for pragmatic reasons
(In basque its: topic focus verb other arguments... the commonest order
is SOV, but this is just because Actors tend to be topics etc), and in
the austronesian languages the trigger must go last, but "trigger" is
not a typical grammatical role so much as a focus/topic marker (I think
its more focus, but as I understand it its difficult to separate the two
in Tagalog etc). In languages where focus and topic are the most
significant determiners of word order, are there any tendencies or
universals? For instance, something along the lines of "If the focus
typically precedes the verb then...." or other statements along these
lines? It seems to me that classifying languages by how topic and focus
affect word ordering would be about as valid as classifying them
according to what order is the commonest for the Actor, Patient and verb
(Btw, why don't we say AVP instead of SVO etc?)