So I want to swap out at least two of the three single coils in my Fender Strat to give it a wider range of tonal options, and also so that it compliments my new tube amp I'm getting for my b-day.

Anyhow, I was thinking of throwing a Hot Rails in the bridge for any metal purposes, like Iron Maiden, but I was wondering... I've stated 1000 times that I love Eric Johnson, but is there a decent pup that would fit in the middle or neck pickup? I was thinking HS-2, but if anyone can suggest an order of pickups that seems fitting, that'd be good. I need blues, metal, classic rock and well, anything really. Perhaps even some jazz.

The amp I will soon have will be a Blackheart Little Giant, I am fairly confident. Perhaps a Fender amp of some sort.
I'd put a DiMarzio chopper in the bridge, I like it more than the hotrails, it's got a bit more output.
Yamaha RGX 520FZ
Squier Affinitys Strat (customized!)
Johnson 620 Player Acoustic

Boss HM3 hyper metal
Boss CH1 super chorus
Zoom G1X

Peavey Valveking Royal 8
New: Peavey JSX Mini Collosal
Hmm, okay so...

I want something like a single coil sized bucker in the bridge... so I will look to that but the tones I want most are EJ, YJM and Maiden. So what about a Hot Rails/DiMarzio in bridge, a YJM in the Middle and an HS-2 in the neck? That would put me up to 2 DiMarzios in my guitar. Dang, this is confusing. Keep in mind that new pups will be boughten at different times, I'm just outlining right now.
the hs-2/hs-3 would need a decent boost pedal to get a decent chunky metal tone.
Not trying to second guess you here - but have you tried out a guitar with the rails? The one I tried sounded, just bad - maybe I got a crap pickup but it didn't sound at all like a humbucker. It managed to lose all characteristics of a single coil while simultaneously sounding nothing like a humbucker. I'm not a metalhead but I don't think the one I played was suitable for even Maiden.
I was using a rails in the bridge of a strat >> 808 clone >> classic 30.
I've done some searching and seen some videos and it's quite possible I had a bad pickup. Demos are impressive so I guess just try it out.