I read them. But you were complaining about the logic of Natsu eating other elements, and then justifying it was okay for Gajeel because Natsu did it.
Either it is okay for both, or for neither. For me, it's okay for both.
As for contradicting stuff in the manga, that's how it always happens. "You could never defeat me!" -- defeated. "You cannot reach that place in time!" -- reaches that place with time to spare. Characters had misconceptions that something could not be done. That something was done. That is pretty much standard.
But Natsu is the main character. It's like expecting Goku to lose against King Piccolo because Master Roshi did, or Ichigo to lose against Aizen because Yamamoto did, etc... it a manga trope. The young hero will surpass the master and become the strongest thing alive.
Also, that fight to run from was Acnologia, I think.
I do think that Iron and Shadow are a more interesting combination, because they add versatility to Gajeel, while Fire and Lightning only add extra brawn to Natsu. And, like I said, I like Gajeel, and I want to see him do stuff too. I didn't like how he was pushed aside in the tournament. But I understand that this is Mashima's story, and Natsu, Lucy, Erza and Gray will be the main characters, in that order, until the end. I'd like Gajeel to be there too, but alas, I take what I can get.
---------- Post added at 09:36 PM ---------- Previous post was at 09:01 PM ----------
Dragon force will come. Against dragons. Or stronger opponents than measly Sabertooth.
If dragon force comes now, what next? Dragon force II? Super sayajin dragon force? Let the man be creative. Iron-Shadow seems a lot more interesting, visually, than stronger attacks due to dragon force.
And before that, I want to see dragon "drive." Sting and Rogue's first power-up. I want to see Natsu and Gajeel enter "drive" mode and kick ass. Then, later, dragon force.
More power-ups will come. Let them come at their pace.