Ok it is well acknowledged that necro as a primary is a bad choice if you plan on pvp. 1) it doesn't afford you the benefits of other classes really good energy managment primaries 2) people don't die in pvp often or well timed enough to make up for a larger mana pool or casting long casting spells quicker.
I suggest this for soul reaping, make it so at level 12 it stops the negative regen on necro pets. Thus allowing them to stay around longer. If you really wanted to do it you could boost soul reaping high enough to make pets regen their own health, but given the random nature of soul reaping it wouldn't make up for the sparatic energy that can be a blessing when low but if you have a full energy bar does nothing for you regardless of what level of soul reaping.
I don't think this would be game breaking as you would, at a minimum have to invest 9 levels worth of attribut points + your facial scar, +a +2 attr rune (which is -50 hp) or a +3 (-75 hp) rune. At that level you wouldn't be able to max out 2 other attributes and i think you can do 12 and 9 if you had to have another maxed out stat. This also would make necro primaries that would like to do pets more viable in pvp as they also require a death on the field which takes more time to wait before you can be effective and takes a long cast and a hefty mana cast for your necro primaries. This also would make Necro primaries more efficent in pet management since they wouldn't have to keep on healing pets just to keep them out.
Finally I would like to point out that necro pets become wild if their master dies, making the pets a scary thing to have out as if your team is around them when they go wild they will wreck havoc. I would say that once they are masterless their normal degeneration goes back into effect.
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). I pretty much cast spells constantly during any battle with only 41 energy, and the only prim I can think that would help that would be Ele, since a Mes fast caster would make energy management even harder.