неол., одобр., жарг. хороший, правильный, надёжный ◆ «Чёткий пацан» — правильный пацан: он живёт «по понятиям», чтит авторитетов и сам является примером для других — как мифический пионер, походить на которого старались советские дети… «Виртуальный музей гопников», 2011 г.
https://ru.wiktionary.org/wiki/%D1%87%D1%91%D1%82%D0%BA%D0%B8%D0%B9

Maybe "really guy" or "right guy," dude.

Cool dude - клёвый чувак.

Да, четкий парень это не клевый чувак))
Спасибо. Убираю.

Though четкий has a definite slang meaning 'cool/good/great', четкий парень may not be a very good guy. I don't know how it's used nowadays, I just can judge from what it meant in the days when I used loads of youth slang words. Четкий парень - he who has some problems with law/connections with crime world, he always has a lot of money in his pocket, spends time in bars/restaurants/etc.
Well, четкий парень could be a hooligan and simultaneously really not bad as a friend.
I still also assume that четкий парень was used just as 'cool dude', because time has passed, meaning of the words can change, maybe someone used it as a 'good chap', it's quite possible.
I definitely don't insist that четкий парень is a kind of hooligan, it depends on context, whom that was told about, who told that and what they meant.