That is a tough color of brick to work with. I really like the example below. It also has pillars like your beautiful home. As you can see in this example the pillars are white.

Exactly, I'm having a hard time suggestioning a color because of the brick but thank you! I like this as well

"Mint green" can mean different things to different people so you should show a sample of what it means to you and Granny. Also, you should say exactly what you're painting. Will it include the brick? Without knowing the exact color, I'll venture to say that it does not sound good to me. I'm imagining something on the low class side, as colors go.

To be sure, what is killing any potential the front of the house has is the hedges lining the walk. It is negative to the maximum and no matter how you trim it, it will remain so. Ditto for large shrubs in front of windows and porch. Just plain grass at both sides of the walk would be vastly superior. We can't see the yard, but based on the hedges, I imagine the general landscaping is in need of a major overhaul.

Nothing wrong with mint green, but its not going to up the resale value if grandma ever decides to downsize. If she likes it, go for it though. I have a friend who just repainted her house bright pink with kelly green shutters. Its unique and she will enjoy it while she is alive, you only go around once. The landscaping looks like it needs work as YV said. Grandma may be tired of doing all the work so either needs to install something way more easy to care for, or get some paid help. Easier said than done I know.