I've been thinking about this for a while now, but I'd like to advocate for Electric/Ground, since some of the better ones are taken already
Passive damage weakness: Meh
The only thing Electric/Ground has going for it in terms of strength is a Stealth Rock resistance and Sandstorm immunity. It's susceptible to everything else, and that includes priority attacks not name Bullet Punch.
Good overall STAB combo: Easily Applicable
We all know how good EQ is, so let's just skip that part and talk about how Electric attacks cover it. They actually seem to tackle Flyers and Levitators quite decently, and also help this Pokemon tackle bulky Waters... not named Gastrodon, that is.
STAB that cannot realistically be spammed endlessly for maximum impact: Applicable
Gliscor and Landorus are biggies in stopping this STAB combo cold, as are Grass-types, however few there are that function effectively in OU. Ground-types can also waltz in with an Air Balloon, forcing this Pokemon to run coverage just to pop it.
Lots of weaknesses and resistances: Applicable
Notable resistances include Rock (Stealth Rock) and Steel (Bullet Punch), in addition to an immunity to Electric, which renders this thing invulnerable to Thunder Wave. A Flying resist helps against Hurricane, but the Poison resistance sees no use. In terms of weaknesses, Water, Ice and Ground all see a ton of usage, making this Pokemon risky to maintain on the field. An additional Grass weakness doesn't help matters.
STAB on notable risky moves: Applicable
Firing off ANY Electric attack can result in Volt Absorb, Lightning Rod and Motor Drive activating, which is a big boon on any opponent. Wild Charge is risky in and of itself since the user takes damage, and Charge Beam not only has major power issues, but also the problem of not always giving the user the Special Attack boost, which is the main reason why it's being used in the first place. Ground attacks wouldn't be considered risky in general if it weren't for the number of Flyers and Levitators in OU, but a Technician boosted Bone Rush can out-damage EQ if it hits 3 or more times, as well as potentially breaking Subs.
Passive damage weakness: Meh
The only thing Electric/Ground has going for it in terms of strength is a Stealth Rock resistance and Sandstorm immunity. It's susceptible to everything else, and that includes priority attacks not name Bullet Punch.
Good overall STAB combo: Easily Applicable
We all know how good EQ is, so let's just skip that part and talk about how Electric attacks cover it. They actually seem to tackle Flyers and Levitators quite decently, and also help this Pokemon tackle bulky Waters... not named Gastrodon, that is.
STAB that cannot realistically be spammed endlessly for maximum impact: Applicable
Gliscor and Landorus are biggies in stopping this STAB combo cold, as are Grass-types, however few there are that function effectively in OU. Ground-types can also waltz in with an Air Balloon, forcing this Pokemon to run coverage just to pop it.
Lots of weaknesses and resistances: Applicable
Notable resistances include Rock (Stealth Rock) and Steel (Bullet Punch), in addition to an immunity to Electric, which renders this thing invulnerable to Thunder Wave. A Flying resist helps against Hurricane, but the Poison resistance sees no use. In terms of weaknesses, Water, Ice and Ground all see a ton of usage, making this Pokemon risky to maintain on the field. An additional Grass weakness doesn't help matters.
STAB on notable risky moves: Applicable
Firing off ANY Electric attack can result in Volt Absorb, Lightning Rod and Motor Drive activating, which is a big boon on any opponent. Wild Charge is risky in and of itself since the user takes damage, and Charge Beam not only has major power issues, but also the problem of not always giving the user the Special Attack boost, which is the main reason why it's being used in the first place. Ground attacks wouldn't be considered risky in general if it weren't for the number of Flyers and Levitators in OU, but a Technician boosted Bone Rush can out-damage EQ if it hits 3 or more times, as well as potentially breaking Subs.