Originally Posted by
Endus
I mean, the first two games were based on 2e, so it's not surprising that they'd base the new one off the current 5e.
That said, even if you haven't kept up with D&D, like you said, 5e is very streamlined, in terms of mechanics. The main thrust of the design was getting away from 3.X's "I have eleventy billion modifiers, let me do some calculus and I'll get back to you about what my attack roll is", into something that didn't slow down gameplay.
Somewhat obviously, that's less of a factor for a video game, which can handle all that math natively, but I'm interested to see how they capture it.
There's basically two concepts in 5e that might translate into the game; bounded accuracy, and advantage/disadvantage.
Bounded accuracy basically means that attack roll/skill check bonuses don't go up every level; they're tied to a "proficiency bonus" which starts at a +2 at level 1, and scales all the way up to a whopping +6 at level 17+. If you're proficient with a weapon/skill, you get that bonus, in addition to what your ability score gives. It's simple, standardized across all classes, and means even at level 20, enough standard Goblins can still pose a threat. This is generally "good", since it narrows the power scale a bit. You get way better at stuff by higher levels, but it happens because of having better class options rather than just better numbers.
Advantage/disadvantage is what I think won't make it in. In 5e, if something is a positive benefit, you generally gain advantage on the roll rather than a number bonus. Same for penalties; they're usually made with disadvantage. If you're blind, you attack with disadvantage, for instance. If the enemy is vulnerable, you get advantage to hit them. And so on. The system works by getting you to roll that attack roll/skill check twice. If you have advantage, take the better of the two rolls. Disadvantage, take the worse of the two. Having both advantage and disadvantage cancels each other out, and they don't stack; having 4 sources of possible advantage and one source of disadvantage means you make a straight roll, without either. For pen-and-paper, this is all VERY fast and streamlined and works really well. For a video game, I imagine they'll translate this back to straight numbers, since you can provide finer gradations; 5e wanted to get away from that to streamline table gameplay, but the video game's systems streamline it inherently by managing it behind the scenes, rather than asking the player to calculate it themselves.
Beyond those two concepts, 5e is really thematically similar to prior editions, and if you haven't tried it, I definitely recommend it as a system. My group's been using it for a while and we're really happy with it.