Ah, but balance, there is. Whilst you can counter almost all of the bulky offenders, to their extent shows balance.
Empoleon, Togekiss, Machamp, and Scizor, are the ones that virtually all sets are countered, or a special set made specifically named to beat a Ghost/Steel in order for them to win. This can be done through simply resisting and walling, just using things like Burn, or just attacking in order to easily beat them.
Suicune, Starmie, Latias and Jirachi are ones that all tend to carry Neutral effective moves, and have either a way to power up their offensive capabilities, or have things like Starmie's STAB Hydro Pump or an HP Fire Carrying Latias to do damage, but all of these can be taken out various ways. For Suicune, Toxic Stalling, and if they are a Crocune, they could be taken out with a physical attack quite decently (my idea has a whole Mixed attacker thing to it, so this is more dependant n what really turns out.) Starmie getss hit by STAB Ghost moves, and will probably go down with Shadow Sneaks faster than it can recover and attack. Latias is very easy to take down if you switch in on Draco Meteor, and can be taken down with relative ease. Without that -2, you can still attempt a Toxicstall with Pain Split for recovery until you can just Shadow Sneak a kill. Jirachi really depends on the set, but if its locked into a NVE move, its pretty much forced to switch out or face the conseqences. Will-O-Wisp can always help on any Physical variant, too.
Gliscor and Swampert, well, not much can be done about them, but you can slightly hinder their goals. Neither can toxic, and to this point its unboosted EQs that are the most that can be taken. Will-O-Wisp and toxic can hinder either, but beyond that not much.
Heatran,and TTar are ones that most sets will cause trouble, and if they have +1 Speed from Scarf and DD respectively, they make life terrible. If 4x moves are available, and assuming you can take a hit, its only barely managable. This assumes you can OHKO with said X4, which won't always happen.
Metagross is impossible, it just can sponge you, resist you, and Q you to death.
It can take down almost everything one way or another, its just all a matter of the set you're running.