I added a lot of bushes around the plaza, because nothing was blocking the area. That way it has sort of a barrier from the station and everything else. I mean you can't landscape the plaza or train station though and I'm not really a professional at it.
Of course, I don't think anyone can claim that title, unless they're paid lol.
My plaza is basically in the same spot as TheDuke55. I just put cedar saplings, bushes and flowers all around it with a little pathway out of clovers up by the bullied board that lead into the train station area. Do you have the dream suite? You can check out my DA (listed in my signature) to see it.