i think that all time ranking should be back. because i personally play from almost de beggining and there are many players who plays for a long time and i want to be fair for all.

I can see your point in this but I can also argue the fact that it may not really be skill but merely a measure of time played. I think you can imagine how that could negatively impact newer players.

i guess the all time ranking must be about wich battle is harder. for example...many players with very high winning streak are dwelling at lvl 16, 17, 18, 19. I, for example, play at lvl 30 +, where the battle are much harder, i play against expericenced opponents, and i dont have such high win streak. so , from my point of view, the all time ranking must include the all time battles and the level wich the players are battleing.

all the damage done over the whole career.

something on the lines of the ELO system:

The Elo system was invented as an improved chess rating system and is also used in many other games. It is also used as a rating system for multiplayer competition in a number of video games,[1] and has been adapted to team sports including association football, American college football, basketball, Major League Baseball, and eSports.
The difference in the ratings between two players serves as a predictor of the outcome of a match. Two players with equal ratings who play against each other are expected to score an equal number of wins. A player whose rating is 100 points greater than his or her opponent's is expected to score 64%; if the difference is 200 points, then the expected score for the stronger player is 76%.[2]
A number represents a player's Elo rating and increases or decreases based upon the outcome of games between rated players. After every game, the winning player takes points from the losing one. The difference between the ratings of the winner and loser determines the total number of points gained or lost after a game. In a series of games between a high-rated player and a low-rated player, the high-rated player is expected to score more wins. If the high-rated player wins, then only a few rating points will be taken from the low-rated player whereas if the lower rated player scores an upset win, then many rating points will be transferred. The lower rated player will also gain a few points from the higher rated player in the event of a draw. The rating system thus is self-correcting. A player whose rating is too low should, in the long run, do better than the rating system predicts and thereby gain rating points until the rating reflects his or her true playing strength.

This system would actually keep it fair for everyone regardless of what level they are playing at... it ranks solely on skill with very little room for error

more info here: http://en.wikipedia.org/wiki/Elo_rating_system