Yeah, this mod was absolutely amazing back in the summer. And back then, I would have agreed with your "best game ever" statement. I still love DayZ and I love what DayZ has done for the zombie survival genre (The War Z alpha starts Monday and The Dead Linger alpha starts on the 31st, both of those were in development before the DayZ mod came out, but DayZ has forced both of those games to take a hard look at themselves as well as push the games out as quickly as possible, not to mention with DayZ's success, games like TWZ and TDL have grown immensely in support). There are the normal problems with an alpha mod like DayZ that we experienced from day 1, such as random deaths, random broken legs (then having to crawl 2500 meters to a city and hope a friend can get in and out with morphine without dying), and the game evolving from an amazing survival game to all out PvP everywhere where people just bum rush you with axes (super realistic, lol). I am eagerly awaiting the standalone and if the price of it remains what Dean has mentioned it will be (around $30), I will be pre-ordering it immediately to support Dean and the game. That being said, I am one of the many many people who have stopped playing the mod because of too many run-ins with blatant hacking. I will take the abuse from bugs, glitches, and exploits of an alpha mod (that's a big part of the fun of being part of a game community from alpha until past release)...but, as far as I've read, the Arma 2 engine is just too easy to hack, so the mod will never really be secure. Dean has said that one of the most important parts of the standalone game is going to be combating hacking, so at least he knows it's a huge problem. TL;DR - Yes, way too many hackers in this mod, hopefully the standalone will remedy this. Check out The War Z and The Dead Linger for a couple more zombie survival games coming out this month to tide you over until DayZ standalone is released.
