I hate to just suggest what I have but there really are some good reasons for looking at it.
May I suggest the Ibanez RGT42 as it has everything you're looking for:
1) 24 frets
2) H-H layout with 5-way switch
3) Pointy superstrat design
4) Super fast and thin neck
5) Locking trem
6) Mahogany body though it is a rosewood fingderboard instead of ebony
7) VERY easy access to the upper frets due to the neck-thru design
It usually goes for £500 but checkout this place:
http://www.guitarampkeyboard.com/en/66779they have it available for only £398 and for that money it's a steal for a neck-thru guitar. This is the first neck-thru I've ever owned and as a main guitar, especially for Metal and Rock, I'll never play anything else again. I simply can't express how much I've loved this guitar. The standard pups are decent enough but let's face it, whatever you buy it's likely you'll ultimately put a set of BKP's in it, that's what I've done. Every guitar I've had before there has always been some sort of niggle but I'll keep this one until it falls apart. I spent £500 on mine and for a little more I could have got an entry level Prestige model but I wouldn't even think of changing due to the neck-thru and to get a neck-thru on a Prestige model you're talking £1000 and I'd still end up changing the pups.
Can you tell I like this guitar :D