1949 S Wheat Penny Question

The Wheats of the 1950's had more die issues those years because of the over use past retirement dies. The small die chip above the 'B' is probably the beginning of a crack or die chip on that area. (BIEs) are found in the area between the 'BE'. But it maybe just starting. On the reverse there appears to a lamination or a struck though debris on the other area you mention. It appears that the stem and area above the grains still has an area that hasn't peeled yet. (thus a raised are under the last 'A' on America. The USA area looks like there was a slight amount of grease on the other devices in that area. It didn't block the devices, just weakened them a bit. (Note on the affected areas, the devices are a bit wider because of the grease preventing the tops of the devices from forming)
Here is what the BU ones look like: