Here's my spin on it: rogues are among the better strikers in the game and warlocks are somewhere near the middle of the pack...after getting their revisions last year. And as pointed out, there really isnt much of a synergy in their attributes. It's going to be a bit of a mush.
There are ways to make a workable Hybrid out of the mix, though. If the PC has Shadow Walk from his warlock side, the Hidden Sniper feat will be a good boost to his accuracy- essentially a full time +2. And while that won't pump his damage per strike, it WILL boost his strikes per combat.
In addition, there are some hidden synergies: some of the warlock powers reduce the defenses of targets...that some of the rogue powers target.
There are ways to make a workable Hybrid out of the mix, though. If the PC has Shadow Walk from his warlock side, the Hidden Sniper feat will be a good boost to his accuracy- essentially a full time +2. And while that won't pump his damage per strike, it WILL boost his strikes per combat.
In addition, there are some hidden synergies: some of the warlock powers reduce the defenses of targets...that some of the rogue powers target.