So, this is quite the topic within the My Hero fanbase. I just want to give my own opinion on this.

Kaminari and Mineta are nothing alike. The only thing that the two share is their love for girls, however they approach it differently.

For example, before Kaminari battled against Shinozaki, he mentally commented on how cute she was, he even did the same with Nejire.

Whereas when the Big 3 introduced themselves to Class 1-A, the first thing Mineta did was stare at Nejire's chest. He even tried to peek on the girls changing and when they were at the hot springs.

This shows that Kaminari is respectful towards the girls, whereas Mineta is not as he only wants to satisfy his lust.

Now, it's pretty obvious but yes I do prefer Kaminari over Mineta like most others, but not for the reasons above and not because of their differing designs.

I like Kaminari because of how funny he is, as his character is like the wannabe cool guy type who would easily trip over his own shoelaces, then there's his Quirk. I do like electric based abilities and the fact that Kaminari can short circuit his brain and become an idiot is honestly hilarious.

Now this doesn't mean I don't like Mineta's quirk as it has a lot of uses like traps and can be joined together to form a sticky whip which is smart.

And that's all I've got to say on this matter.

In the end, I think it's kind of a problem to compare two characters by just one quirk they share (pun not intended) and not looking at what makes them different from each other, as they have different roles in the theme and idea of the series.

Though as much as I hate Mineta, I'm not against a character arc where they need to put aside their desire and to focus on what's right, an example of this is Subaru from Re:Zero. But I don't like the fact that Mineta's desire is so in your face and not agreeable.