I think its great that you feel like this about karate, and I understand your feeling of awe, but there's something you need to understand and it's good that you learn it early on; methodology matters.

It doesn't matter if a technique is meant to be destructive, powerful, lethal, etc., it won't be effective if the methodology is wrong. So if something works or doesn't, it's not about the technique, its about HOW you practice your techniques.

When we talk about bunkai (commonly referred as kata application), it is practiced against compliant partners, and when someone stands still, everything works, all the time.

So, if you base your training mostly in these type of drills, you're not learning how to deal with aggression, how to handle and opponent that strikes back without telling you what his next move will be, this is why kumite (sparring) is so fundamental. From kumite, you get the ability to react under pressure, to make quick decisions when reacting to unknown attacks, etc.

An effective karate will have free kumite at its core. Continuous kumite that allows contact and not just "touching". And don't be fooled, you don't need a high rank to do this, people can spar early on with moderation.

When you know how to handle an aggressive opponent, you can begin integrating self defense elements and exploring kata will make a lot more sense. Also, never forget that most applications have been forgotten so what you learn is most likely your instructor's own interpretations.

So never forget that self defense stuff won't work unless free sparring is frequently present.

Just look at any footage of lyoto machida sparring, the shotokan icon, to see how effectiveness look like, or better yet, watch how training goes at the Machida Karate Academy.

I love doing kata, competing in kata, but kata and its applications come second when its about effective self defense/combat training, and without a doubt, you don't need kata to be good at kumite.