Buy some studs and add them in to make it 16" on center. You're drywall will hold up much better and your insulation will be easier to install.Yeah, 24’ OC
You can also caulk the gaps between the studs and exterior wall as well as the floor plate where it meets the concrete to help keep out drafts or bugs. You can see the caulking between the studs and exterior sheathing. It makes a difference and it not expensive to do, just time consuming.
, it's already time to sell this house, my youngest graduates HS in May.