How difficult is it for a widow to apply for and receive VA benefits upon the death of her spouse?

I won't bore you with the details, but in 2009 I was classified as rated 80% disabled but granted 100% disabled due to inability to work due to service-connected disabilities. I've never been "happy" with the way the VA has handled my situation as there is no true classification for my condition because when I was diagnosed it was extremely rare. It's never been an issue for me - I was tired of fighting the VA and writing Congressmen trying to get them to look into the matter. My thing was I suspected the condition was more common than folks realized (post-concussion damage to the hypothalamus) - particularly with all the concussions our guys were getting from IEDs in Iraq and Afghanistan. But there comes a point where you've done all you can reasonably do, take your "win" however it was achieved and call it a day.

The thing is, last year I was diagnosed with lymphoma and after chemotherapy I am now in remission and on the mend; but it got me realizing I needed to put my house in order, so to speak. I never gave much thought about VA benefits for my wife being much of an issue as I knew if I passed due to a service-connected condition she was eligible for at least part of my VA benefits.

Then late last year an old Army buddy of mine, who'd lost both his legs in Grenada and was definitely 100% disabled died and his wife had some trouble at first getting her widow's benefits. It got me to thinking about my own wife and whether there was anything I could do or am I fretting over nothing? I'm gathering a packet of my DD214s and VA Letter and other relevant documents she might need. As I said, I'm not happy with the way my letter reads, but I don't know if there's anything at this point I can do to make it read better. Do I need to go for 100%? Is that necessary? It took 23 years to get them to do what they did and do I risk screwing it up for no reason by filing an appeal (and Lord knows I'm tired of that)? Is it even necessary? I turn 66 next week.

How important is the "letter" in the process anyway. My TBI isn't listed, just the residuals from it. Just wondering.

I intend to visit my Alabama Department of Veterans Affairs Office within the next week or two, but wanted some input from fellow veterans - I don't even know if I know all the right questions to ask and hoped some input would help - and maybe even help other veterans in the same boat.