In terms of atmosphere/appearance, I much prefer Pandora. I really wish they had incorporated some vegetation into Galaxy's Edge--there's a reason luke spent his life dreaming of leaving Tatooine to join the resistance, and it's not all noble ideals. The whole "desert outpost" vibe is so blah, and it's weird that of all the gorgeous planets in the Star Wars movies, THAT's the look they went with.
I also prefer the Pandora quick service. Much more innovative, and no, I don't think calling fried chicken and mashed potatoes "tip yip" makes it interesting. Ronto roasters is more ambitious, but with basically one menu item it's much too limited.
BUT with all that if you asked me to choose one land and drop the other, I'd pick Star Wars over Pandora. The roaming characters in Galaxy's Edge add a lot, I like what they did with the shops where there are lots of little marketplace stalls ("pet" shop, clothing etc.) rather than a big single gift shop, there are lots of hidden details to enjoy once you get over the overall bland first impression, and while each one has a steller e-ticket attraction, the second "family ride" in Galaxy's Edge wins out over Pandora.