No response in the newbies section so i'll try here.
What makes a wave/freestyle kite (rrd type 9) bad for freeride?

Well bad is interpretive. You can freeride with a wave kite as well as a freestyle kite. Think of a Vegas. Great in the surf and for free riding. But if you are talking about the kind of big boosting hooked in freeride stuff then there are better kites for this approach. Wave kites and freestyle kites will take you vertical but drop you just as quick unless you loop and move the kite. Can't comment on the rrd never flown it. That's it really. A freeride kite say like the rebel, the edge etc will take you high and give you hang time. A wave kite or a c shaped kite will not give you that hang time. But in the right hands and with the rider working with the limitation of these kites for freeride will do just fine. A very good rider it doesn't matter really. They could freeride a paper bag with string attached. The early free riders rode kites not dissimilar to this description compared to modern kites.

I have just swapped from a switchblade to a drifter this season which took a bit of getting used to as flies a lot different, but that my free ride sessions have not changed much and still get great boosts but have to say you do have to move the kite around so as not to drop like a stone. Loving the wave style of kite though.