A new thread did not have to be made for this, but since it was made i'll answer.
The string gauge suits the tuning you're using not the genre you're playing. If you're in E standard .009-.049's or .010's will do fine. Go a tad thicker if you're playing lower. It's also preference, the higher the string gauge the more tension you will have, but if you switch drastically you will need a set up.
have you checked out any other pickups? It's all ear, what sounds good to you might not sound good to anyone else and vice versa. I would suggest going to a local music shop and seeing if you can try out multiple other guitars with different pickups. I myself would never want an invader in my guitar. I'd stick to JB/59 combo honestly.
Also, tone is going to come mostly from your amp not your pickups.
Seriously though, if i could have any guitar in the world right now, it would be the Washburn WM526. it's pretty much a USA custom, with an OFR, EMG's and a carbon glass epoxy fretboard (which is incredibly slick), great fret access, super fast neck and amazing build quality.
Well, if you're looking for someone to say yeah i'd buy it, i'm probably not the best person to ask. Personally i wouldn't buy a non-prestige ibanez, nor would i buy one that's shaped like that. I like the shape, i just wouldn't play it myself.
the OFR would cost 150 by itself and more to have it installed unless you did it yourself.
It's your call, its good price on the guitar but i wouldn't buy it personally
metalcore (along with most -core genres) is becoming plagued with clichéd, generic, repetitive, boring bands that are somehow all getting signed and pumped up our asses. I'm not by any means condemning the genre's as a whole, but the record labels need to wise up and stop the over-saturation of CRAP
fretlesses usually give a different sound than than fretted and might not be the sound certain bands are wanting, i dont think of it as any worse although i wouldn't want a fretless in my band. In Obscura (band not album) it rapes however.
EMG's sound terrible through solid state amps (well not terrible, but not anywhere near good), especially not a 15W spider. I like ESP's but not low end ones. An ESP Alexi is just going to be more expensive because it has his name on it, you could get a much better guitar for the money.
It would seem that every djent band says that their somewhat influenced by Meshuggah so I would say yes. This is old news thought. Djent was a cool new thing when it was first brought to everyones attention, but just like deathcore it's been overplayed, and genericized and the greatness that it had has become plagued with terrible crap.