We're keeping a close eye on Feral in PvP and understand the concern. Things currently on our radar include the Berserk duration, the Unheeded Warning trinket, and the Predatory Swiftness talent.
That said, we're happy with Feral performance in PvE overall. It we were to nerf Predatory Swiftness, it'd have a minor impact on PvE. Unheeded Warning is both a PvE and PvP problem. The particular mechanics of the trinket keep it disproportionately powerful for Feral druids. Nerfing Berserk would have PvE ramifications, but we'll take steps overall to make sure your dps doesn’t drop in PvE. We do everything we can to ensure we're considering all aspects of gameplay when approaching class balance.