Are you gonna run stretched rubber like some of those pictures?

F no.

Wheel flairs? You need to be careful about your wheel size then. You can run a wider wheel with stretched tires (even though they look like your pants are too short IMO) because they fill the wheel wells differently. If you are going to run a regular wheel & rubber combination then you can get too wide for the wheel wells pretty easily 

I just want to figure out the max size for a stock suspension lowered 1.5-2" and probably with an air dam. No flares, no aftermarket coil over setups.

I might do something to give it camber but otherwise I don't think it'll be modified.

25" is the stock tire diameter, right?