This originated as a thread response.

The best voice acting is the type that doesn't feel tiresome. A lot of the well-produced games out there (AAA) like Ubisoft's Far Cry and Assassin's Creed games have well produced voice work, but it all sounds like the same generic and tiresome shit after a while. The dialogue is overwritten to the point of blandness and the voices are homogenized white men or badly imitated accents.

The superlative voice work, as far as games, comes from GTA radios, anything with Troy Baker/Nolan North (Uncharted, TLoU, Bioshock Infinite), and the old-school dialogue heavy adventure games. My personal favorite is Grim Fandango. Manny Calavera (cred. Tony Plana) has some excellent line delivery that is actually assisted by the story's interactive nature.

Games, being an interactive medium, normally stumble with a certain degree of clumsiness when it comes to V.O. There is a disparity between delivery of dialogue and action, exaggerated further when the player fails to react at the developer's intended pace. This problem was especially observable in PS2 era games when audio compression was an issue. With skillful writing games can dodge this awkwardness. That's what Double Fine (Tim Schafer) did with Grim Fandango.

In all forms of entertainment the burden of actors and writers are lightened by humor. If you can't achieve the gravitas of a perfectly lit and expertly rehearsed Broadway or Hollywood production, and most video games (with rare exception) still pale in comparison, it is best to be funny about it. Self seriousness is crippling. Look at Dying Light with its story as bland and functional as whole wheat toast. At least Call of Duty employs a bit of absurdity. I'm holding out hope that "press x to pay respects" is self-effacement.