Unless you're going at fuckoff absurd speeds (an appreciable fraction of the speed of light), why would you need ladders? The ship doesn't have to be a narrow tube of multiple levels if you're going slowly enough for space dust to not be an aerodynamics problem. You can make a big ole pancake with propulsion on the bottom and it should work fine.
But of course, if you're using this form of acceleration as gravity for years and years then you'll need to be turning around a lot or you will reach those absurd speeds in less time than one might think.