Arenas has his bad nights, he's still developing as a player, and still maturing with his game, remember he's only 23 years old.
With that said, Arenas is a more efficient scorer than Kobe. Out of the Top 15 scorers, Arenas is 4th in TS% behind Brand, Lebron and Redd whole are all killing in terms of scoring efficiency.
Arenas is the best passer, shooter, scorer, slasher, basically eveything offensively except for post scorer on his team. While he does take a lot of shots, he runs the offense, and it's kinda of part of the teams plan for him to do that because their isn't a real post presence, he's the best outside shooter on the team [yes, better than Chucky], is the one that has to spread the floor, but also penetrate and put pressure on the opposing big's, and then also run the offense and create for others too.
Defense is where Arenas lacks. He's not a terrible defender, but not a good one either, he's average at best, but does have the potential to be good. A lot of people don't want to put him in the superstar range because of defense, but Lebron, Tmac when in Orlando, Nash [he's considered on I think], etc are/were all consider "superstars" without being good defenders. Arenas right now is not a superstar though, but he's in the position between All-Star and Superstar. He's better than the All-Star perimeter guys like Redd etc, but not as good as the superstar guys.
One thing that kind of irritates me about Arenas is his shot selection.
The guy takes 7.8 three pointers a game, and while he does hit a lot of them, its always bad to settle for perimeter shots too often.
I agree, but with how good a shooter he is, you can't fault him. He's taking as many three's as Ray Allen, while making a much better percentage this season, that's quite impressive, and even matching Allen's percentages last season. Anyone can take a lot of three's and shoot 31-34%, but he's shooting 37.8%, and before last nights game was at 39%. He's making a case as one of the best shooters in the league.