On the DLC: I remember when they were boxed, came with way more content and added to the game instead of unlocking stuff already on the game. Also known as Expansion Packs, something only a few Dev's still do, like Blizzard. And with the godly amount o' source books for Cyberpunk, little DLC packets are just not gonna cut it in my eyes.
Now for that quote and the words within. He said GTA, I point to San Andreas(again). Large cities, Large game world for it's time. Something more modern, look at Just Cause 2, XBOX HUEG game world some big cities and small towns, villages, harbors, military bases of all sizes and styles. I personally don't think there should be roadblocks of any kind, let the player run off from the mission if he wants. Like if it's a mission to guard some proto-type weapon/armor/cyber-ware, let the player grab it and run like hell with it. I've only seen that happen in one game, the first Armored Core way back on the PS1. Where you were asked to guard a proto-type radar but if you wanted you could take it for yourself.
Though of course there would be world roadblocks keeping you in the game world, like the giant oceans that surrounded the islands in GTA3 and Vice City. In San Andreas they had a mountain range and oceans as roadblocks. RDR had the same thing I believe but also had the more dangerous predators hanging around the edges of the map waiting to pounce on any one fool hardy enough to come snooping around for escape.