doubleKO said:

He was more like a prop played by a martial artist and a voice actor, which limited his potential even more. It wouldn't have been as easy to dub in another voice as it was with Vader. I find it hard to believe that they ever intended to stick with Ray Park's cockney accent.

Seeing as he only spoke in two scenes and an advert I think any mention of the wasted potential of a trilogy of films with Peter Serafinowicz's voice being the prominent villain is as moot as it is tragic.