After playing for about a dozen hours now I still have some issues with the game, but I'm definitely enjoying it more. It's so close to perfect but the issues I have below really keep it from being a game that has the longevity and feeling of inhabiting an environment I found Grand Theft Auto IV.
The Big Stuff I Want Rockstar To Tweak
1) The ability to go into PRIVATE games with friends only where you can tweak the game settings to your liking.
2) Tweak the speed of horses! Sprinting on horses is TOO fast. I think the fastest they should be able to go is when you get to max speed WITHOUT tapping A to sprint (depleting the gauge). Also, make the sprint gauge more important. It regenerates too fast, and depletes too slow. When you use it, the horse goes too fast, so either slow that down or make the gauge deplete faster across the board. Since there are so many fast travel options available to us, the speeding bullet horses make the land feel too small (even though it isn't).
3) If our own horse dies don't let us whistle for a random new one. Just make it so that we have to grab a wild horse nearby (there's always one close by no matter where you are anyway). It's goofy that I can just whistle for another as it lesses the importance of taking care of the horse you've kept with you.
4) INCREASE the speed of trains. It's so silly that you can jump onto a train while running with it on foot while it is going full speed.
5) Use Euphoria like they did in GTAIV and polish up the animation and the animation transitions! I want to see John Marston stumble if a horse walks into him just like Niko did when a car slowly pushes him. I want to see horses fall over, or at least react, when I hit a tree or a big boulder. I want to see the horse struggle more when going over rough terrain. As it is, it's just a standard running animation while the horse and legs barely change and the model only goes vertically up and down.
6) Make falling from heights more significant instead of a WAY TOO QUICK landing animation that barely slows you down. Make the character look like he actually fell from the roof of a bulding and has to take a second or two to get up/recompose himself before continuing to run. The game as a whole is much quicker than GTAIV, which is fine, but in many ways they sacrifice immersion for it. Find a balance Rockstar! And make sure not to make EVERYTHING too fast or else events like falling from a horse or a cliff loses its significance.
7) More NPC's in free roam mode. Their absence is pretty disappointing. :[
8) This one is less important but: give us the ability to sit down on chairs/benches. They make an amazingly detailed world but limit the interaction we have with it. Why can't we walk around while watching a movie in Armadillo, for example?
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Aside from the fact that the game feels a little unpolished when it comes to the animation and the speed of the game feels way too fast at times it's just about everything I hoped for. It's an amazing game with so many strengths, but some of the things above really do keep it from being close to perfect in my eyes. A lot of what I've posted isn't even that hard to implement or that far fetched since some of it we've seen in GTAIV.