I don't think DAI's exploration was as bad as some say. I can see why some think it's very boring. I do think considering this was Bioware's first grand attempt at open-world they did a good job in many areas. The focus on environments that look very different is my preferred way to do games like this. I don't want one huge world that looks similar all over. The art direction was fantastic and often a major flaw in open games is they don't reward you very well for exploration. A visually varied game feels far less repetitive to me regardless how fun it is to explore. Bioware does a great job at rewarding you even in the most obscure corners you'll find treasures, lore or relevant banter with companions randomly. It's downsized compared to a game like Skyrim which is also something I preferred because when you have massive open areas you get overwhelmed exploring too easily something I never felt in DAI. Could it use a lot of improvement? Absolutely. I'd say it's no worse than other open-world games and in some ways better. Very few I can say were able to shield against the flaws DAI presented.
All that being said, I'm happy to see Bioware will not be doing DAI exploration in ME:A. That comes straight from Flynn's mouth. He said ME has their own identity and while the game will be heavily focused on exploration it will not be similar to DAI. Hence why they added the Mako because they felt they could easily improve on that experience from ME1 and deliver the promises it never fulfilled. ME:A has the potential to be genre defining in their exploration when you really think about it. Can you imagine a sci-fi space game that expands the limits of your imagination? I'm hoping No Man's Sky on PS4 will do that for me and I really hope Bioware sees the potential this genre can do for open-world exploration. They have the opportunity to do something no other devs have done and I'm most excited they're no longer on bottlenecked PS3/360 hardware which Flynn admitted had a huge impact on how they're doing exploration over DAI. You could tell DAI wanted to do things but was bottlenecked due to being included on old hardware.
The potential is there so hopefully Bioware doesn't squander this opportunity at innovation. I would think that after all these years they're doing everything they can because this game has been in development what seems like forever. I know it's not their longest project yet but you have to think this studio is vastly bigger so for a project to sit in development for 4+ years it's going to be BIG for them. No doubt it has a higher budget than DAI because it's easily a more popular franchise.
If I had to pick a game to emulate then obviously it would be the favorite among many in Witcher 3. It was very narrative focused on the side missions. If you peeled back that part of the quests you'd realize they were just as repetitive as any other game but it's the narrative that made it unique. Ironically, Bioware has their own examples of this in the past yet they did not use it in DAI for some bizarre reason. CDProjekt just did it in a masterful way. I'd like to see it extended even further by making each planet feel 100% unique and you could easily do this by making environmental hazards play HEAVILY into the gameplay.