When it comes to the train, it depends on different things. Of course, noise coming from the tracks is a big thing, but I live fairly close to the tracks, and I do not hear it as much as I possibly could. As long as you get a well built home for the noise, you should be fine wherever you are.
One other big thing is getting caught by the train when trying to cross it onto and off of Wellborn Road. There are not that many ways to turn, so you will just have to wait most of the time.
As for how the new high school is, my younger brother goes there and he has nothing but positive things to say about it. As for the staff, I personally know many of them and they are really good at what they do. In addition, the school provides some other things that Consol does not offer, such as the culinary classes, which is by far my brother's favorite class. I'm not bashing the Consol teachers, but the CSHS teachers are really working their tails off. I talked with one of the teachers, who was once my teacher at Consol. She told me that in all of her years of teaching, this is her busiest one yet. She is enjoying it, but she is definitely earning her paychecks.
The best thing to do for you is to roam around the south side of town to get ideas of each community. I've done that myself, and there are many positive things about the area.
Best wishes on your search and making your wife a happy wife.