THEORY: two questions

Hey all.  Adam here again.  So lately I've been inspired to spice up
Doraja a little bit, adding a couple or three more interesting features.
For instance, I now know that the aspect morphology which previously
only occured on verbs now also occurs on prepositions; I've also worked
out a new script which I'll hopefully be able to scan someday.  However,
before I can continue with this interesting-ization, I have two
questions for the language experts here on the list.

Question number one. Is there any typological correlation between word
order and head-/dependent-marking tendencies?  That is, would a
head-initial language be more likely to be head-marking or
dependent-marking?  Same question for head-final languages.

Question number two. I've decided that Doraya verbs need to have some
sort of agreement with their dependent NPs.  However, I'd like to have
something more original than a simple agreement with the person of the
subject.  Any ideas for something more exotic?

Thanks for your help,
Adam