Congrats on your new baby! That must be both so exciting and yet also difficult with PCS.

Can't really speak to your last two questions, but in reference to #1, you might want to check out a Huffington Post article called "The Interesting Case of LCD Screens and Post Concussive Headaches" (I can't post a link yet).

In the first few months of my concussion, I really struggled with screens, particularly with my computer screen. I basically stopped using my computer to prevent the symptoms getting worse. I could tolerate my iPhone much better. This exacerbation of my symptoms by the computer eventually went away after about 3.5 months after my concussion (by contrast, I could use my iPhone with no issues about 2.5 months after my concussion). I can now use my computer without any problems (a little over 4 months after my concussion). I think it definitely has something to do with the smaller screen/less pixels.

(As an aside, it was always interesting to me how some sports med doctors I saw who specialized in concussions were completely unaware of this very disabling problem - one just told me to turn down the brightness on my computer and "keep practicing" with the computer, as I needed to "get used to it").