It sounds like you have travelled from California, and have been previewing houses in the Northeast Tarrant County area. One has to wonder if you were working with an Agent, and if so, why you are not seeking advice from that person, instead of throwing out an overhead question on this website. And if you were NOT working with an Agent, then why not? Anyone who is thinking of investing a considerable sum of money in a house, needs to engage a Realtor to represent them.
As a Realtor who has been selling homes in Keller, Colleyville, and Southlake for 33 years, I can tell you that this is one of the best areas in the country to get a fabulous home at a very reasonable price. You can have all the features you desire, with a pool, a media room, a 3-car garage, a large wooded lot, and all the extra rooms your heart desires. But the key thing that will determine the resale potential is the location of the property.
Keller is a large town, and there are many nice areas that are not so close to the railroad tracks as to be noticeable. There are some absolutely gorgeous homes in Keller. Perhaps you should take a look at the 76244 zip code as well as the 76248 zip code area. Buying a house near the tracks may seem like it is just a personal decision, and a question of how long it might take you to "get used to it." But you should stop and consider the problems you may have when you go to sell the house a few years from now. If it is causing you this much pause, it will certainly affect other buyers as well. And that is just the type of thing that makes a house take longer to sell. When a house "takes longer to sell", it typically will sell for less money than a similar property in a different location, ie., away from the tracks.
So, do yourself and your family a favor, and get with an experienced Agent. Stick with that person until you collectively find the right house for your family. You can't really go wrong buying a house in any one of the cities you mentioned. Real Estate values in North Texas have been very strong compared to the rest of the country. ...And they will continue to do so.
Best wishes to you and your family,
and welcome to Texas!
ULTRA Real Estate Services