Wenger's future at the Emirates Stadium remains clouded with uncertainty, with the Gunners fifth-place finish in the Premier League meaning they will miss out on Champions League football for the first time in two decades.
The Frenchman, who joined Arsenal in 1996, has faced calls from some sections of the club's supporters to step down at the end of the season.
The north London club exited the Champions League at the round of 16 stage after a humiliating 10-2 aggregate defeat to Bayern Munich, leaving the FA Cup as the only piece of silverware they can win this season.
Wenger, whose contract expires in the summer, has suggested that his future will be decided at a board meeting after the FA Cup final.
Redknapp told Sky Sports that Arsenal needed "fresh ideas" to move forward, but stopped short of calling for Wenger to step down.
"I still feel someone would come in, freshen it up and there would be a buzz in pre-season. Otherwise the players are going to be like 'OK, same message as last year'. Sometimes you need to hear a different voice," he said.
"There's an issue around who would make that call, though. He's the only manager in the world who decides whether he stays or goes and it shouldn't be like that.
"Perhaps he will step aside if they win the FA Cup final. And he has a great opportunity to bow out on a high."
Wenger drew support from an unlikely source at the weekend, with former Manchester United manager Sir Alex Ferguson warning that Arsenal could find it tough to replace the Frenchman.
"It's quite easy to say 'Get rid of him', but who do you get? Who do you get in to keep that club the way they are for the next 20 years?" the legendary Scot told BBC.
"I really feel sorry for him because I think he's shown outstanding qualities, and I think he has handled the whole situation. I don't know many that have done that."