That's
really not the case. Killua wasn't afraid of people because of their power. He was afraid of people he wasn't confident that he could win. You really need to rewatch the scenes related to Illumi's needles and Killua's previous fights if you have such a ridiculously serious misconception about his character.
Killua states that his normal attacks couldn't damage the bombers. Do you think he would have any will to fight if his motivation for evading an opponent was "Oh, he's stronger than me"? That's just one of his parameters. While he does evaluate someone by their aura output, he is not shy at all of fighting stronger opponents so long as he can seek a plan to victory, and he's actually happy the bomber isn't weaker than him because that allows him to toy with him for longer and test his new tricks.
Gaara's sand particles aren't getting through Killua's ken/ryu, and if they do, he's noticing them immediately since an aura user can feel and control their aura like it's part of their body (it's the principle behind En). Gon has been shown deflecting attacks with Ren when he had just learned it, so sand particles have really nothing on Killua.
What kinds of intelligence
feats Gaara has? Because if we're really just speaking about "oh he did ranked missions", then goddamnit, Killua is a fourteen years old kid who became something one in a hundred thousand highly prepared adults can become, excelled at it with a talent of one in ten million people
among those who get to use it in the first place and outsmarted a fuckton of adults who were considered above average for his group. He is so insanely talented he literally disregarded the need of experience in a feat of precise nen application that would have required both experience
and talent to be accomplished. Gaara is more experienced? Killua ***** on that with wits and talent.
Are we talking about how many stuff Gaara did while young? Let's speak about how many assassinations Killua had already completed as a five years old — or at least how he at age eleven had already killed more people than a trio of hunters who were shown killing dozens or hundreds through thousands of people in the Greed Island arc — or as he got as high as anyone without nen could ever get in the martial arts old with eight years of age. His experience with fighting isn't just superior to Gaara's: it's
overwhelming. I really don't see how you can argue in favor of Gaara being more intelligent — comparable is already a stretch — with everything Killua has done.
But at the end of the day, I'd disagree with even that: it doesn't matter how many times a character has fought or how many adults failed at what he did: what allows us to have an insight into the level of experience of a character is his
feats of intellect, and in Narutoverse as a whole the levels of strategy showed up until that point are really not as impressive as the amount of reading into a person's trains of thought, knowing they will be cunning and set up powerful batman's gambits, and worse is the fact that as the series go on we get less of that and more of hax, so there really aren't many combat intelligence and experience feats you can say Gaara profits from or scales to.
But in Hunter x Hunter? We have Genthru instantly guess Gon's train of thought, what he's wary of, his plans and practically read into his mind out of sheer understanding of himself and others due to sheer massive combat experience, then we have Gon outsmart genthru and we know for a fact that Killua is smarter than him due to several showings, including defeating another one of the bombers with much greater ease. Narutoverse doesn't have this shit.
And we also must remember that the important thing about experience is not how long you've been in the job, but how many tricks you've learned from that experience and how many different things you have experienced. That's why Goku, regardless of being a fighter with decades of experience, isn't regarded as someone as experienced as, say, Sora from Kingdom Hearts, even though the latter doesn't have in age what Goku has in fighting experience.
So no, Gaara is not as smart as Killua.
Votes still at the same markers:
Killua Zoldyck — 6 (
Unforgiven0815,
Jesterofgames,
Mand21,
ZackMoon1234,
Calaca Vs and
Hagane no Saiyaji)
Gaara — 2 (
Dariel Senju and
AstralKing7)