Little slow on this poll, so let me bump it by explaining my own choices...
Seems like all three voters so far agree on a Fly speed for the swarm, and a Land speed for the coalesced form. I imagine it as something like a swarm of bees that occasionally can gather into something a lot more solid.
Land and Climb speeds in the swarm form are rather redundant, if it already has a Fly speed anyway. Given the way a swarm moves, maneuverability isn't really an issue. Might be useful if it could alctually move faster on land than in the air, but given its diminutive size, that's very unlikely. Diminutive single creatures typically have a very small land speed, although they can have a fairly respectable Fly speed.
Swim and Burrow to me seems like it would make more sense for the more "solid" coalesced form, so I put them there. I also decided *not* to give the coalesced form a Fly or Climb speed. I thought it would be more fun if the creature occasionally had to switch back and forth between swarm and coalesced form to pursue its prey. Climb a tree? the creature switches to swarm and attacks you in the tree. Jump into the lake? The creature coalesces and jumps after you...