Here's my two cents, which is probably what its worth. Many years ago DH and I had booked a
DCL cruise using Dreams as our TA. I decided on that trip to get the agent to book us a week in WDW as well, since I had always booked WDW by myself this was all new to me. Then I had several other families wanting to meet up with us for our week at WDW and they asked me to book for them and make any needed arrangements. I booked their packages myself, no point in getting the TA to do it. It was all good.
Then out came free dining. You know that you often have to jump on this deal quickly or your room/resort could be sold out. I sent off an email to our TA requesting she look into this for us and make the change. It was hours before I heard back from her and it was a mass email, looked like it was sent to all her clients, stating she knew the deal was coming out, please stop emailing her. If she could get the deal for any of her clients she would let us know then. If she couldn't then sorry.
So while I waited for the TA to get back to me with an answer I managed to get my other families reservations changed right away. We did end up getting the free dining on our reservation but it was a long 24 hour wait before we were informed. I could have made that change and not worried about it myself IF I had owned the reservation.
I will never use a TA for booking WDW again, I don't like the feeling of losing control of it. If a deal is coming up I don't want to wonder if the TA will be to busy to get it for us. There is no advantage for me, I can do everything they can. So can you.
Also, I have a local TA I sometimes used for travel to other countries who had the Disney Certificate that was issued saying she was a Disney specialist. She had been to Disney ONCE! You really don't have to do much to get that certificate stating your a specialist so if your using one ask questions about their knowledge.
If your worried about the long distance, I downloaded Hangouts which is a app that allows you to do long distance. I have used it to call from serval countries, saves a bundle.