1) He didn't get one-shotted. I just said he got defeated.
2) Yes he is.
a) Natsu vs Zeref
b) Natsu vs Jacob
c) Natsu vs Neinhart
d) Natsu vs Larcade most likely
e) Natsu vs Zeref definitely
Erza is getting the spotlight too with Ajeel, Neinhart and in the future with Irene. Not to mention, the plot is revolving around them. Mashima has such a diverse world with characters of so many different personalities yet recently he has been majorly focusing on this tiny group only.
3) Ajeel should've been done with them by now. Nothing but plot excuse to hold him down.
4) Not to mention Mashima could just make Mirajane take-over which will hide her boobs and actually make this a proper fight. But no, obviously plot is making Jacob look even more stupid.
5) That's what the translation says.
6) Tbh, I don't. So far, she's been used as nothing but a plot convenience to save the characters.
7) Wendy has shown absolutely no skill capable of healing Juvia on that level. Juvia literally gave away her blood to Gray, how the hell can Wendy heal her? If she did something like replicating blood, I'll call it an asspull.
8) I'll clarify this later. I didn't mean ignored or all side characters.
Of course this is all opinionated, so I don't mind if you disagree.