Foster has earned widespread praise for his impressive performances between the sticks this season.
"I still think Ben can get better and better," said Kiely to the WBA website. "He was 30 yesterday and for me the years between 30 and 40 were my golden era.
"It's exciting times for both him and the football club.
"My golden era was at Charlton and it wasn't a coincidence that my family was settled and I liked the club.
"I played my best football there for those reasons and I think Ben is in a similar situation here.
"Everything seems to fit. It seems to suit."