These house below are from ALYS Beach and they are contemporary Mediterranean style.

The addition of colored wood shutters and iron exterior lanterns seems like it would help your mother's home besides painting it white.

Painting it cream will go a really long way to improving the looks. Put pretty tile on the porch. Plant up the square with the tree, so every inch has something flowering in it, get some pots of plants to put on either side of the door.

9 Architectural Elements of Spanish Revival Style

White paint. Decorative shutters of some sort for the upper windows. Spanish tile around the front door...or a stencil of tile.

Here is a sketch of my concept...rough drawing.

Shutters may soften the look.
Consider repeating the first floor grills on the second floor windows.
Large house numbers on blank space at left of door,and large lush planters flanking the door.
Some iron embellishment (but not over wrought iron!)could also add a decorative element between the top windows.

Some great suggestions. To add onto what rosiembog suggested, perhaps the decorative element could copy what you have on your window grill.