Yes, I think those are good goals. Goal setting is not easy for some people. So, okay let's see if we can break these down a little bit more.
1.) Have exchanges periodically with her via text that are not negative
How much do you text her now? It is difficult to keep things upbeat once lawyers enter the picture. My suggestion is to make positive statements regarding your son. Start with that. As you think about things from time to time, jot it down so you'll remember in case your brain dries up.
2.) Have her notice ANY difference in me at all
That one will be a challenge since your contact will be limited, especially visual contact. As with most, you feel anxious about her noticing, and b/c you feel time is escaping before you have a fair chance to prove yourself. But if you focus on changing back to the man you once were (or better), it will show in your communication and she'll hear from others also. Bear in mind that the main thing is to make life-long changes, and for your sake......and the rest will follow.
3.) Exercise enough discipline to limit conversations (text, mostly)
My suggest is to set your watch (if it has a timer) to keep yourself aware of the length of time you've spent communicating, if it's by TM or voice. If by email, etc., you may give yourself a certain amount of lines to write and then close. I think your hardest part will be in "responding" to her text. Allow yourself no more than three responses at one time. When you begin to have more control....then cut it back to two responses at one time. That includes one word TM's.
4.) Get out and LIVE and see if she notices
The big part is getting out and living! In order to do that, you need to start with an activity calendar. Write in something for every day you don't have your son. Don't spend it all with your relatives. Make it about you and what makes you feel good. Also, during the holiday season, reach out to help those who are in real need and you see a way to help other than just giving money to a cause.
What's going on around town that you would be interested in?
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!