I’m not Craig, but I’ll take a stab at it.
If you’re not aware, to get the maximum life of your AGM batteries plan on discharging them no lower than 50% of their stated capacity. So at 220ah rated total you have 110ah available. Lithium batteries are a different story. The good thing about AGM batteries is they tend to have a lower self discharge rate, thus better storage life. If your solar array is regularly deployed that may not be much of an issue for you.
The closer to the batteries part is because the smaller the gauge of wire and/or the farther the terminal use is from the source, the more electric power that is lost to resistance in the wire.
I can only guess bad way for coffee is the amount of power. I’m fine with automatic coffee. My camp system won’t run a coffee maker but I’ll certainly bum from those who’s system will.
As for inverter size, most RV style microwaves I’m familiar with are 900-1000 watt. I have no idea what a blanket takes. Using the microwave as the anchor point, I’d look for a 1500 watt or up for no other reason than I’ve rarely gone wrong by getting stuff with some extra capacity. Somewhere on here are a couple discussions on inverters. What I remember from them is it’s not a 1 to 1 ratio of DC in to get AC out. True or not? I don’t know, hopefully those more knowledgeable on here will share.
Good luck with your decision.