Hi Naif, 

It looks like you have introduced some sort of tilted optic or an asymmetric optic into the system, and that's why it is not behaving symmetrically. Whenever you add an element that tilts the rays that depart from the optical axis, the way to correct the aberrations from that surface is to add an element that acts opposite to that element (if you can). Otherwise, you need to identify and look closely at the surface that is causing the dominant aberration. 

Having said that, as you can see from my answer, the aberration correction strategy is not only about looking at the resulting spot alone (you spot diagrams don't have a scale bar, so it's impossible to compare). Try looking at the Ray Fan diagram to see what kind of aberrations are present. Also, try looking at your entire optical system to see where aberrations may occur. Remember, there are patterns to aberrations and their correction strategy. For example, to decrease distortion we need to balance the power of the optics about the stop, and for spherical aberration we need to balance a positive lens with an opposing negative lens. 

Try to observe your entire optical system to see where the problems are. If you can't find anything on your own, post again here and we can help (if you can disclose your optical system). Good luck!