Would 400 CC Moderate Plus Silicone Implants Look Normal on 5'2" Woman?

can be done with wider implants.  As for size, 75 cc's is a very minimal amount that won't produce much change in volume.  But with wider implants, you will be giving up some projection.  A diminished intermammary distance can be achieved but you must be careful to not create the 'uniboob' or symmastia.

Unfortuantely the attached photo is not helpful to me in addressing your question. An unclothed photo, if possible including one from before surgery would be useful.

If you breasts are naturally far apart, they will be far apart with implants, which need to be centered behind the nipples and areolas.

Particularly when we use under the muscle implants, by far the preference of most surgeons, the insertion of the pectoral muscle into the breast bone limits how close to the center the implants can be placed even were one to ignore areolar position. 

It is more difficult to achieve cleavage with implants as compared to natural breast tissue of the same volume.

I doubt that larger implants will be the answer to the issues you present. Discuss carefully with your surgeon, and if needed a second opinion. All the best.