I scoff at Ground being a "best all-around." Needs to be switched with Psychic in Forsety's list thingy.
The primary problem with Psychics is they have a lot of problems with multiple popular pokemon. Metagross itself walls (or outspeeds and 2HKOs) a lot of them, Electivire can put the hurt on a lot of the dual types, Tyranitar is the bane of many of them. Psychic itself is a pretty lame STAB to have. Infernape slaughters the Steel/Psychic contingent.
Contrast that to Ground, where everything can belt out a 100% accurate, 150 post-STAB BP move. Grounds also have an inborn electric immunity and a useful resistance in Rock. Psychics resist... other Psychics, and Fighting (half the time). Combine it with the fact Grounds have a few traits that offer additional immunity (Levitate, Water Absorb), and with some specialized EVing you can work around your biggest problems. There are a few floaty psychics, but if you've got to stack half your team with Base 600s just to avoid getting OHKOd by a mediocre attack, it says something about the efficacy of Psychics. I'm quite certain Azelf/Jynx/Cresselia/Metagross/Starmie/Jirachi is an awesome team. Loaded to all hell with Legends, but awesome nonetheless. The Psychic crutch is Legends. Now, I'll admit Ground uses Garchomp -it's all it as access to in 600s-, but it relies on more than just blatantly overstuffed stats. If you wanted to play by Footnote's no 600s idea, Psychic mono would be little more than a load of glass cannons and middling special walls, with some extra cred to Slowbro, Claydol, and Bronzong for being able to stay in a little while and not being killed by 6 different kinds of attack (I'm lookin' at you Eggy).











