I'd switch to flex and zone. I'd do it right away.
Those are in my view the most basic schemes to run and you can be okay with them with the least practice at the systems. Do it soon, this season isnt going to be a winner anyway,
I'd do man defense, but with weak DEF ratings that will be a problem. Even though I'd do zone, I would still make adding good DEF a priority. And ATH.
If you dont want the transition, you could bail on this world and find a team in another world that already runs something other than FAST/PRESS and work from there. I think any offense other than fastbreak and either man or zone would be okay. I'd go man cause I like it, but either okay