Unless they're one of the super dwarf varieties, even the Weigelas are going to end up being at least 3 to 4 feet tall and wide I inherited an obviously non-super dwarf Wiegela. 3-4' wide is a serious understatement unless you prune religiously. Ditto the 3-4' tall. You might want to find out if the Fire Department has the right to prune your Wiegelas, should they decide they're overgrown. And whether the local government has a policy on what you can plant near a fire hydrant, and how close. I live on a state road (little 2-lane blacktop, 45 mph semi-rural school bus route) and it's amazing the rules for the 20' of my yard adjacent to the blacktop. Completely different rules for uphill and downhill situations, downhill being more stringent. And if they don't like whatever's growing there, they just chop it off with their long-armed Blade of Death and Destruction. No warning ahead of time: just however the driver decides to interpret state law on your particular stretch of road that morning. Weeping cherry overhanging the road? Not anymore! Brush too close to the side of the road? Just cut it off at ground level! [It wasn't my weeping cherry, and the lifelong-resident neighbors who own it didn't even notice some of it was shorter -- but they were shocked at what I told them. The trimmed brush belonged to the neighbor farther north.]

i recently built a dry stack circular stone wall around a large pin oak in my yard the wall is 32 inches at its highest point. I am worried about the roots of the oak pushing upward on the wall and destroying it, although i did do some intense labor around the areas where the roots were the most visible. I purposely postioned the rocks in these areas in such positions that there is room for the roots to grow before touching the stones........... time will tell.

"... would you do a straight line off of the front walkway or something more rounded? This is something you'd work out in plan view. We can't see enough detail in a perspective photo from a single angle.

Veronica, given that you are in Georgia there are likely big thunderstorms? I would say that a wall would be useful. Bushes will only help control erosion a little bit and they'll take a while to get established. Other advantage of some kind of stone or hard wall is that it could help provide privacy plus act as seats (while people view and enjoy the fire). There's lot of materials available, including genuine stone blocks, cement (fake) stone, concrete wall, bricks, wooden beams, etc. Here's an idea with stone...