I fully respect your opinion but I'm pretty much on the opposite end of the spectrum on pretty much all regards. But again, I say this as someone who's been a huge fan of the series for years and years.
I was reeled in from the moment I found myself in the midst of a blizzard, trouncing about in foot-deep snow and it's all been epic ever since. I'd say the toughest moment came really early when I was briefly overwhelmed for a day trying to figure out how manage all the new things I was expected to do. But now it's all pretty much second nature.
I also love the deliberate nature of everything. The story really heated up for me around Chapters 5 and 6, to the point where I just wanted to play the next mission to see what would happen next, but prior to that, I'd struck a pretty great mix between advancing the storyline and just living my life out there and handling whatever I encountered. Sometimes it was canoeing down some rapids, sometimes it was a day of fishing, and sometimes it was just pure exploration, with Arthur's camera at the ready.
Regarding the story, on account of it being a prequel, I reckon a lot of us experienced a sense of predictability, but for being a video game - and a Rockstar video game, no less - I found the storyline riveting and enthralling, relatively speaking. It's not Citizen Kane, but I was fully invested in my character and those around him by the end. But, again, as a huge John Marston fan, I admit it wasn't going to take much to make me happy.
I admit I also probably would have never considered any controls issues if I didn't read people complaining about them on the internet. Upon consideration, it's not terribly difficult to imagine a smoother system in multiple regards, but I also never really had the controls negatively affect my experience. Sometimes the cover system wonked a little, but it never ruined anything, for one example.
Perhaps our differences are best quantified by the fact that I thoroughly enjoyed even the "boring" missions. One of my favorite moments in GTA V was the time I got to mop the floors of the FBI office and there were some moments like that in RDR 2 I enjoyed just as well.
TL;DR - Different stroke for different folks
Comment