#1
I play an Ibanez RG3EXFM1, and I decided it's about time I replace the Vintage 6 & 7 pickups that it comes stock with. I've come down to a combo I like, and as I know the bridge about should be higher than the bridge ouput. But I don't know how large the difference should be. The choice of pickups I have is the following:

DiMarzio Fred DP153 placed in bridge, output of 304mV
and
DiMarzio Evolution Neck in neck (obviously), output 296mV

I was just wondering if the output gap is too little, if it is, if I should go with the Evolution bridge at 404 mV output with the Fred in neck.
#2
The difference doesnt matter that much, you can adjust the height of the pickups to compensate for the difference. The difference is pretty small, but you should be able to compensate enough.
#3
its a myth. depends how soft you want your neck pickup, and how heavy you want you bridge.

i have an X2n in bridge and a airnorton in neck. i changed the height to get the levels right and there is NOTHING negative to say about it at all.

X2N = 510mV
ANorton = 270mN
*Enter Sig Here*