You can't really compare your experience on the different cruises. The weather, the currents, the tidal cycle all have a much greater impact on the ship's motion than the location of the cabins.
Base on a simple law of physics, the location of minimum movement will be the center of gravity (CG) of the ship. In general, an object in motion will tend to pivot/rotate around its center of gravity (CG). So, regardless of the overall ship's movement caused by tidal, weather and current forces, the CG of the ship will experience the minimum movement. The further away from the CG, the greater the movement.
The CG of a ship is typically along the center line between port to starboard, slightly aft of the mid ship (because of the engines and the fat stern compared with mostly empty & narrow bow), and about 1/3 of the way up from the bottom of the ship.
I don't have a profile of the ship to show how deep is the draft. But, my guess of the CG would be around Deck 2, just aft of cabins 2085/2585. Depending on the actual location of the engines and gearing, it could be a bit further forward or aft; and, depending on the actual draft, it could be a deck higher or lower.