Stop in for a cup of coffee

I have a backyard buddy free standing four post hoist. I never thickened the concrete,and yes,the floor cracked. In the first month. No change since. 5”thick maybe.
But cracks extend out from the corners of the floor drain,should have thickened it to bottom of drain.

So if floor is cut,and dug out deeper,what is used for cement?
Is extra steel added?

I should have added a couple 2x2” reciever tubes for tools.
Toolpost sockets are handy.

Thanks for the feedback. I like the idea of a moveable lift as they do take up a lot of room. I'm not sure what will need to happen to beef up the lift area. What I'm wondering about is a sanity check on the builders advice of adding it later. I do want to save money, so can't see pouring the whole foundation with extra thick concrete. I'm wondering what concrete/construction to ask for during the initial build. Would rebar be used and will that make adding the lift a pita in the future? So much I don't know...