Consider OSAKA Metro Day Pass (1-Day or 2-Day Pass) to ride not just the Osaka Subway but also Osaka city bus. Also, benefit from discount coupons at about 30 attractions across the city including Osaka Castle and Tsutenkaku Tower.
Another option is the Osaka Amazing Pass (1-Day or 2-Day Pass), or use an ICOCA card purchased from vending machines at subway stations that will simplify your Agenda in Osaka.
I really don’t recommend driving in Osaka but do it if you want to visit hidden gems outside the city.
Anyway, my general advice is try to use trains as much as you can, even around Osaka. It is a simple and efficient way to travel in the Osaka region