I don't feel that the gore and nudity was a very important part of Elfen Lied's popularity. Afterall, Gantz was released the same year as EL and featured even more gore and nudity. Yet Gantz was mostly disliked outside Japan. Elfen lied's fandom is 10X the size of Gantz's internationally. Rather than just focusing on tits and gore, Elfen Lied used tragedy, psychological drama, and dark romance to tell a moving tale with themes of prejustice, hatred, guilt, love, redemption, and forgiveness. This is why EL has a massive female fanbase while Gantz...not so much. If anything the gore and nudity hurt EL's popularity. If they were removed it could have aired on Adult Swim in the US and gained the popularity of Full Metal Alchemist, Death Note, and Code Geass. fans of Gantz on facebook =47,000  fans of Elfen Lied = 433,000. If gore and nudity was the important factor, those numbers would be reversed.

yeah, I think I agree with you. The gore and the nudity are the factors to be somehow settled if EL should be remade or newly made/modified. Otherwise the creators will just repeat the same mistake. (well, I do not want to use the word "mistake" but because of  my limited vocabulary I can not recall other proper words.) In the manga world, that kind of gore and the nudity were ok or accepted, but in case of animation, it's a quite different situation. US or Europe must be much stricter than in Japan.

In case Lucy can not use the gore as her "tools" of showing her anger or resentment, what would be the alternative means for her to do it, I wonder on the other hand... (yk)

It is a complexed problem. The brutal violence was there to underscore the series' dark themes. I don't think a remake should remove  ALL of it. However, this violence could be portrayed with a LOT less blood and gore. Perhaps Lucy could break people's necks or cause strokes or something rather than always cutting off heads and limbs and making people explode. The comedic scenes with naked Nyuu could be easilly cut back without really damaging the series. The diclonius at the facility were kept naked by the research staff to dehumanize them, because animals don't wear clothes. The scientists justified thier cruel treatment because they considered the diclonius as sub-human and mere animals. European viewers seemed to understand this and not raise a huge fuss about those scenes, but many American viewers thought that those scenes were intended to be erotic simply because nudity was there. American viewers even complained about the Lucy and Kouta swimming scene, which was NOT intended to be sexual or erotic. We Americans can be difficult in that we too often believe nudity = pornography. I grew up in a city where religious groups keep putting clothes on all the classical Greek statues. I do think that if the comedic nude scenes with Nyuu were cut, less people would complain about the other scenes with actual reason for featuring nudity.