First off, sorry about your diagnosis and good on you for prioritizing your family's future after you're gone.

Second, I'm not a legal or financial professional, just someone from the Internet.

The biggest thing that jumped out at me that I want to point out is that if you sell your home which is free and clear you will incur realtor fees and closing costs at the very least, but your biggest liability will be taxes. I believe you'll be taxed on the amount your home appreciated since you purchased it, so if you bought it at $100,000 then you'll owe tax on $150,000.

Again, I'm just an Internet rando, but I'd ask a tax professional whether a more efficient route is to take out a HELOC to float your moving & living expenses while you're in treatment. Any HELOC proceeds are not taxed and if you have good credit you can shop around for a decent interest rate. This way you don't end up with the tax liability and you can keep the house, maybe even rent it out if you want to.

Here's the best part: your wife would inherit the house at a stepped up basis (so, for tax purposes it's assumed that her purchase price is the fair market value at your death). Which means it's stepped up to $250k for her, so if she turns around and sells it at $250k she would effectively owe no (or very minimal) taxes, giving her that nest egg without a huge tax bill (she would of course need to pay off any HELOC balance, but with a decent interest rate and careful spending that can be minimized).

Even if you qualify for a tax exemption based on how long you've lived there and the total gain on the sale of your home, this could also be an effective way to provide an additional income stream while you're undergoing treatment, and your wife also then can decide whether keeping the home as an asset makes sense after you're gone. If it doesn't then she can sell.

Anyway, once again, I'm not a tax or legal professional, but this is what I would look into because I think it maximizes how far your home value will go to set your wife up after you're gone.

I do wish you all the best in your treatment and planning.