My first AR, one of the first runs from S&W (stag?), has a fantastically worn standard milspec trigger. It's not too heavy, not too light, breaks pretty well for an average idiot like myself. It's not a target gun, nor is it a race gun, but it does serve duty as a HD/range gun that has faithfully set off primers for the last 10 years (or so?). Nothing wrong with a milspec trigger, just take it out and shoot it. If that's not adequate, you can take some flitz to it and have OK results without worrying about removing too much material. The ALG or various enhanced "standard" triggers are probably good options, but I've never experienced them, so I'll defer to those that have. From original manufacturer or the EE, you're really not paying a ton to get one and try it out. Hell, if you don't like it just put it away in the parts bin and BAM you'll have another AR in a few months....
Aside from the various milspec ones that have come in my lowers, I do have a little time with an MBT, some CMC single stage triggers, and some time finger fondling a geissele SSA. All are good feeling triggers, but for a pistol blaster the returns are relative... I have been a bit of a fan boy for the MBT though, for the price it's really a fantastic two stage.