Mixed order any good?

Hi all!

I have an unassembled Freeguild griffon and 10 Ellyrian reavers.

Order seem to have the widest range of figures and I am tempted to throw together a mix of units to make something unique and/or crazy.

Is mixed order effective or do faction bonuses matter more?

Where would you go from what I have to 1000pts or does what I have not even work together?