My team is almost always fixed to include Grass, Fire, Water, Flying and usually Electric-type Pokémon. I like to rotate the sixth slot with a Pokémon of the type I need at the moment, ensuring that I always use a Pokémon of each type at least once... and with once, I mean ONCE in the entire game. For the reminder of the game, that sixth slot is usually a Fighting-type, a Psychic-type, a Dragon-type, a Ghost-type, or a Poison-type. Currently, in my Y, that sixth slot is being filled by a Dragon (my good ol' Garchomp).
The types that I use the least are Rock, Bug, Normal, Fairy, and Ice. Also, I also prefer to use Ground and Steel-types only when they're paired with something else (like Garchomp, who is Dragon/Ground and Empoleon, Water/Steel). I use Ground-moves a lot, and the Steel-typing provides good defences against most other types.(except [mostly] Ground itself!)
I tend to use Rock-types for HM slave purposes. Most of the time, I won't catch a single Rock-type until I get to the Victory Road, where I'll use it to move boulders and smash rocks.
I'll always catch Bug-types at the forests in the beginning of the games, but I almost always leave them in the PC, unless I need it for some reason (e.g. going against a Grass-type Gym Leader). It's just that they tend to have poor movesets and a lot of weaknesses.
Pure Normal-types are just too... meh... to me. I haven't had the chance to use Fairies too much, and I'm not quite sure about why I don't use Ice-types more often.
The types that I use the least are Rock, Bug, Normal, Fairy, and Ice. Also, I also prefer to use Ground and Steel-types only when they're paired with something else (like Garchomp, who is Dragon/Ground and Empoleon, Water/Steel). I use Ground-moves a lot, and the Steel-typing provides good defences against most other types.
I tend to use Rock-types for HM slave purposes. Most of the time, I won't catch a single Rock-type until I get to the Victory Road, where I'll use it to move boulders and smash rocks.
I'll always catch Bug-types at the forests in the beginning of the games, but I almost always leave them in the PC, unless I need it for some reason (e.g. going against a Grass-type Gym Leader). It's just that they tend to have poor movesets and a lot of weaknesses.
Pure Normal-types are just too... meh... to me. I haven't had the chance to use Fairies too much, and I'm not quite sure about why I don't use Ice-types more often.