While I like a lot of Steel Pokemon, and I understand it and Dark were implemented to balance Psychic, I really think they overdid the amount of resistances with them. For instance I don't think they should be immune to Poison, and I also think Water should be super effective against them for that matter.
I don't like Poison, Bug and Steel types! I hate their moves, I hate them all. lol Not to mention when Poison types poison you!! The most annoying thing!!!!!
You most say you dont like Rock Type Pokemon, well, I don't use them either. I don't hate them. I mean, their powers are cool and they are so easy to defeat haha
luxray is my favoruite, i actually like electric type pokemons that have base attack stat greater than base special attack stat.
btw some friends said that rock type sucks, ok , i ask them ; Have you ever grow a tyranitar ? :D ok i admit that geodude or onix and some others' **** but this is different. this is king of the rock types for me.
Least favorite types would have to be Poison, Rock, and Ghost. I'm no competitive battler, but I can offer my tidbits on why I don't like these:
Poison doesn't offer much of a playstyle other than tanking, for the most part. Plus the massive defensive stats give me problems in almost every situation. In addition, it barely has any weaknesses and no type advantage (except against Grass but Grass is weak to almost everything D: )
Rock is weak to a multitude of types. Their massive defense is usually offset by the amount of weaknesses it has. In addition, Rock-types are usually slow and don't fit my normal playstyles. Tyranitar is probably the only exception to this criticism. (I mean, seriously, it's a powerhouse!)
Never found the need to use Ghost-types...even though it has 2 immunities. Ghost offers no type advantages except against Psychic types (which are also weak to Bug and Dark, which I use quite often) and itself. Ghost also cannot damage Normal-types. Ghost moves are also lacking, mainly because I don't use status-inflicting moves during gameplay. Most of the time there is no need to use Ghost types, when there are other options that my team can use. (Although I think under these conditions, Normal could also fit into my list of disliked types but Normal-type Pokemon can learn a LOT of different moves in most cases)
The Bug-type sucks, but I say that in an in-game sense -- competitively, Bug has U-turn, Genesect, Volcarona, Durant and other examples of sonewhat decent (and cool) Pokemon to use. In-game, though, most of the Bug-types you see are utter jokes -- and there are way too many Bug / Flying-types. Seriously.