We're thinking on a few changes and wanted to get your thoughts as well. Please remember none of these are final.
Overlord speed upgrade moved down to tier 1
HotS has given a lot more tech options to all three races, and we feel scouting is more important than ever. Terran/Protoss already got their scouting buffs, and we felt Zerg could use one too. Keep in mind this isn't as crazy as it sounds because you still need to spend the extra 100/100 resources as well as 60 seconds to get this upgrade in tier 1.
Spore buff vs. bio (maybe 15 +15bio)
Fungal missile speed down a bit more
We think in ZvZ Mutalisks are a bit too dominant right now.We're realizing the Fungal Growth nerf was too much vs. Mutas and potentially not enough vs. other units.
Therefore, we think a +bio buff to Spores will only mostly affect Mutalisks to make room for ground based strategies in ZvZ. And we're hoping this gives us more room to nerf Fungal Growth a bit more. We feel units like Mutalisks, Hydralisks, or Ultralisks received significant buffs in Heart of the Swarm that it's probably ok to tone down the Infestor a bit more.
Oracle Envision duration increased from 30 seconds to 60 seconds
This one is to make this spell a bit more viable.