You might have longish tails with a 7, but it would be a sure thing. on the other hand, There are definitely carries you could do with a 6 (ruck, any hip carry, etc). A lot of people have multiple sizes for different carries and honestly, I think it would be easier to resell a 6 than a maxi. If you're buying new and can exchange, go for a 7. If you are getting used (and if you are planning on owning more than one wrap) maybe a 6 so you could sell or trade for a 7? But really I'm just thinking out loud and maybe you should get an answer from someone who knows for sure.
Re: Girasol sizing for this plus size mama?
I say go for the 7. As long as you aren't getting a fringed gira, you can easily cut it down if you need to without affecting the resale value.
Which one are you looking at?