MA L,
Good insight and good decision to share it with corporate.
If you have a moment I might suggest that you forward a copy of your letter to the attention of the General Manager at the particular stores mentioned.
The reason for this is so that person can address what are called "housekeeping" issues before they impact another customer.
The other issues such as color and wall treatment are best shared with corporate where those decisions are made.
You could be right on the roof leak or it could also be condensate from an HVAC which is a relatively easy fix.
Stop back and let us know if you hear back.
BillR.