Design is not really the same as how the whole thing looks like. But I get what you mean. Still, I still feel that the whole art has degraded quite a lot since the Osaka arc. I reread the previous few arcs yesterday and I must say, I really notice the difference. Also, I feel that this arc can't compete with the previous ones. I loved Gantz during those previous ones, and thought that the Osaka arc was extremely awesome, but this one is not that good.
I'm not calling it bad or anything, just nowhere near as good. It is cool that the mangaka tried to gamble by this whole plottwist, but the speed seems to have gone from the chapters in my opinion. Or mabye it's just because I can't read the chapters continuously and have to wait way too long for each new one...