RE: Mixing Tires, personal experience with a Vanagon.
I'm going to try to keep this brief but it's a long story.  Lead in:  In
1994 I bought an '85 Westy that needed tires.  Went to the local tire store
and they put on a set of Michelin XZX tires, wrong tires for a Vanagon (but
many were put on Vanagons and later Michelin did a recall on those IIRC).
Drove several years with them (wallowing in the wind, didn't know any
better).  Developed a seperation on one tire.  Was leaving on a trip and the
tire store put two new MXTs on the rear.  Felt very little or no difference
in handling.  Drove for a year like that.  Then seperation on another of the
XZXs.  Put two new MXTs on to match the year old MXTs.  I though I was
driving a new vehicle when I drove out of the tire shop.  Lesson: Put the
right tires on the vehicle to start with and second lesson the wrong tires
on the front with right tires on the rear still feels wrong.

Last fall I replaced the Agilis tires on my Westy with Nokian Haka CS.
Nothing wrong with the Agilis just getting down on tread (and were lousy on
wet grass and mud).  The CS are noisier than the Agilis but feel just a tad
more solid.

As for your problem in rotating tires keep in mind that the Hakas may be
directional (my CS are) and would have to be remounted when rotating unless
they are just changed from front to rear on the same side.