http://www.worldofwarcraft.com/info/classes/warlock/talents.html?0000000000000000000002050030133250101501351000000000000000000000
Get this one for crit and then spend next 5 in Imp. Corruption, then next in Mana Feed and Demonic Resilience.
OR
http://www.worldofwarcraft.com/info/classes/warlock/talents.html?0000000000000000000002050030133250103531301000000000000000000000
Get Mana Feed and Demonic Resilience and then next 5 in Imp. Corruption, then next in Demonic Tactics for crit.
OR
One of your own suggestions.