-Lack of items
Alpha/Beta had less items.
-Lack of mobs
Alpha/Beta had less mobs.
-Lack of blocks
Alpha/Beta had less blocks.
Creative mode did not even affect how Survival worked: it's simply a game mode alongside Survival. It allowed creative players to build amazing, wonderful, gorgeous and gigantic creations. Please, explain to me how Creative has affected your survival experience. And don't play the 'It gives you all the items'-card, I asked how did it ruin YOUR experience. You don't want to use Creative mode? Fine! Then don't use it, and ignore it. There is no evil ghost forcing you to play it.
-Commands and Command blocks (Cheats)
I could pretty much give the same explanation here. Command blocks and commands are not even available in survival (without opening to LAN), so how did it affect your survival experience? Just like with Creative mode, nobody forces you to use cheats.
-Lack of ambient sounds
For once, I have to agree with you.
-Just, lack of content in general
...Which is ironic, since you want to go back to the time when Creative didn't exist, meaning less content.
-World generation (bring back the old 1.7.3 and previous world gen, that'd be good)
Honestly, the 'world generation is ugly' argument is an opinion. For you, it might be ugly, but for someone else it probably isn't.
-Lack of sounds in general (or at least good sounds)
Except for ambient sounds, I don't agree with you on this one. There are plenty of sounds for various blocks and mobs already.
So, what's wrong with Adventure mode? You did not even mention it in your post.
-Servers (Survival Servers are fine)
Nobody forces you to play on other servers than Survival servers. Again, what's wrong with them? You did not mention these either.
-Realms (Seriously, Mojang is just trying to get your money)
Realms is pretty much an 'official' server hosting service. Every other server hosting service also wants money for hosting your server, so suddenly that's alright?
-Lack of good game developers (that is a fact... they are probably the reason why the game is ruined)
I'd like to see you program a game.
-Lack of good updates (updates come really slowly and don't do anything. SERIOUSLY, WE NEEDED A UPDATE FOR HORSES. IT'S A SINGLE MOB. 1.9 is probably the best update for a while, except it's taking 8 months to do a few arrows that I can make in an hour)
These 8 months were spent to fix bugs for the game's post-beta versions which you hate so much. Or would you rather play a game that's unplayable because of the bugs? Also, if you are apparently so good at developing software, why don't you make a game yourself?
-Exploring is boring (the surface has nothing, the underground has nothing)
Opinion. I think exploring is very fun, since I'm always searching for epic landmasses.
-Lack of collectables
Alpha/Beta had less collectables.
-Lack of generations
Lack of... What? Generations?
-The way mobs have changed (A.I is absolutely horrific, and all the stupid useless stuff that has been added)
Oh boy, I hope you were not one of those guys hoping that Mojang would finally add lamb chop and rabbits. The A.I. is being fixed, hopefully.
And what I completely despise here is this:
Minecraft isn't about creating maps and redstone structures; instead it is about exploring the awesome (not anymore) world and building cool stuff yourself.
How would you know? How would you know what Notch had in mind when he developed Minecraft? In Minecraft, you set your own goals, nobody forces you to do anything. You want to explore the world? You want to build an amazing skyscraper? You want to develop an epic contraption? Play in a playermade adventure map? Play with your friends on a server? It's all possible. And that's what makes Minecraft special about Minecraft, you are free to do what you want. You too are free to do what you want. Play survival if you hate the other gamemodes so much. Mojang even gave you the option to play the Beta and Alpha options, so go play those and don't moan on the Forums about how Alpha and Beta were so much better.
What if we, the veteran minecraft players already did all of this and are bored of normal games? And no mods aren't what they were before, now we have million copies of popular mods just like factions servers.