well guys i don't know why all or should i say most people hate slaine, but if it is because he shot inaho, then let me tell you why he shot that emotion less guy in the first place, here are the reasons:
1) when inaho was crawling towards the princess, an already devastated slaine, thought that inaho might harm the princess even further that is why he pointed a gun at him and told him to stop (probably).
2) well after he told him to stop it was acctuly inaho's fault that he got shot, because inaho pointed a gun back at slaine, so over here it was shoot or be shot type of situation.
3) the third point could also be because when saline helpes inaho on that island, inaho destroyed his craft causing slaine to be caught , and then being greatly tortuered.
these are some of the reasons why he shot inaho and by the way inaho should be greatful that slaine didn't kill him , and because of slaine shooting inaho in the eye , now inaho has that cool left robotic eye.
i would say that saline is far better then inaho ( don't get me wrong inaho is a cool guy), this is because of his loyalty as well as his love towards the princess is far more than inahos, he knows her since childhood and could do anything for her and we all know how touching the torture scene was, and if anytime the princess says "thankyou inaho for saveing my life", inaho tries to act cool and all, and says that he was trying to protect his life and that kind of stuff he doesn't show any type of feelings towards her, he in my eyes is only trying to help the princess because he and she are only good friends, so slaine is without doubt a really reallly really good and interesting character he is cool, charming, and loyal , he really makes you get touched, while inaho is busy trying to show no emotions and accting all cool, watch the anime 3- 4 times and tell me has inaho showed anytype of romantic feelings towards the princess, the would be a really big fat, NO! And by the way the princess doesn't have anyting except friendship towards inaho, and saline as well. both inaho and slaine are getting higher and higher ranks because of their talent and attacking or battleing skills, so both are doing good.
so what i mean to say is that slaine and inaho have many differences , but both are smart, good at battle, and are good friends towards the princess so both are awsome characters and i see no reason to hate either slaine or inaho. both have reasons for their actions, so i wouldn't criticize their actions and start hateing them ,without seeing what happens next, so hateing a character without knowing why he did ,what he did, makes one look like a anime noob! so tell me are you a anime noob or not?