New to Saint's Row, looking to replay some of the Open World stuff

[Quickdraw Calamity]

Hi! I'm new to the Saint's Row franchise and beat Saints Row 4 last night (fantastic game, btw) and I was wondering if its possible to replay all of the Open World stuff, like the targets, store hacks, minigames, etc etc without having to start a new save. Is that possible through either the game or a mod?

Thanks in advance!

Quickdraw Calamity