Well, they solved it with C4, but honestly I think that while it's surely cool and whatnot, C4 is not exactly easy to come by. You have to really invest a lot of points to get there and then it's not exactly cheap to craft just one of them, let alone couple of them just to be able to open some regular doors to save time, so lockpicks would make much more sense in that area, plus they are much more silent too. In real life you don't normally use C4 to open regular door even with barricades either, so that part was an oversight in my opinion.