5. Dragon
Some of them look awesome, whereas some don't look so great (I'm looking at you Palkia >.>) and their stats are some of the highest, granting about 50% of dragons psuedo-legendary status. Favourite dragons are: Hydreigon, Flygon, Kingdra.
4. Water
Neutral coverage, most can take decent damage and deal it back, most of them also look pretty cool. They also learn the most HMs and commonly have some of the most diverse movepools. My only issue with them is that most of them lack speed in comparison to their other stats. My favourite water pokemon are: Samurott, Swampert, Kingdra.
3. Dark
Decent stats, decent movepool, awesome looks. They generally have that sweeperish feel and can often deal some serious damage. Their only issue is that they can't take hits and its caused by their low defences and even lower health. Even with this, they're some of my favourites: Weavile, Krookodile, Hydreigon.
2. Fighting
Just using them gives you a sense of power as they have some of the highest attack of ALL pokemon. Although there are very few fighting types that I really like, the type in general revolves around my battle style, which is mostly power. They just lack the speed needed to accomplish what I want from pokemon. My favourites are: Blaziken, Emboar, Conkeldurr.
1. Fire
In my opinion, this type provides the best mixed sweepers in the whole of pokemon. Most of them have high attack, massive Special attack and some pretty good speed. They have less weaknesses than they do strengths and they generally have decent movepools, which commonly provide moves to defeat their arch-enemies. Water Types. Also, about 70% of fire type attacks have over 80 base power, making their attacks incredibly powerful with STAB added ontop. However, there are very few fire types and most of them are starters or legendaries (which most people don't use) and a lot of people prefer water or grass starters making fire pokemon very rarely used. My favourites are: Blaziken, Darmanitan, Emboar.
Went into quite a bit of detail there. :P