I'm a little confused here. Most of these suggestions are just plain bad.
The entire concealment pool is pretty much a wasted pick on a PvE build unless you have power picks to spare and need things for LotG mules, but a Widow should has so many powers that can slot LotGs it's not needed.
If you're going to dip into the leadership pool on a Widow you'd honestly only really need Assault and maybe Manuevers. You already get better versions of the entire leadership pool in your secondary, and Vengeance is available in-set at level 35.
I don't think it's "SOP" for anyone to take the medicine pool and recall friend unless you're a "healer" and those are pretty much useless on a halfway decent team anyways. A Widow is probably not going to have room to get three powers deep into the medicine pool when almost any other pool is a better choice.
Rune of Protection is a decent choice if you have power picks to spare. That being said, investing in the fighting pool (why wouldn't you, after all) gets you some solid S/L resistance, a good IO build will get you a modest amount of resistance to everything else except maybe E/N/toxic, and Foresight's scaling resistance bonus means you'll be doing pretty well for yourself once your health gets low.