This is just my opinion based on years of experience. My background is in a Korean style called "Ji Do Kwon." My school is a very "Americanized" version of Ji Do Kwon. In my school, you'd start off with basic mechanics. As you progress, you start kick boxing.
In the 80's and 90's I competed in a tournament league called the A.O.K. This was an open tournament system where all styles were welcome but no matter the style, you still had to adhere to the rules. It was all stand up fighting and no grappling.
I had a chance to fight guys from many different "punch/kick" styles. It was a great learning experience.
Having said that, the only grappling that I have learned has been from the Army and I suck at it.
But grappling is an awesome form of fighting and I respect the grappling styles a lot.
The over all conclusion that I have come to is that it's the individual and not necessarily the martial art itself that is great.
A striker that can't grapple gets taken down by a grappler will lose. A grappler that doesn't know how to bridge the gap will get pummeled by a good striker.
My advice to any Martial Artist is to not get too cocky. As soon as you say that "Kung Fu" sucks...well someday, you might have a Kung Fu guy beat the mess out of you.
Every Martial Art has it's weakness. Every striker style leaves you open at the time of throwing a punch or a kick. Ju Jitsu is great but what if two or more guys attack you? What then?
So what I tell people who are not yet Martial Artists is to take what ever is available. They're all good.
In a perfect world, I'd like to see a real hybrid Martial Art with: the punches of pure boxing, the kicks of Tae Kwon Do AND Muy Tai, and the best grappling techniques from Judo, Ju Jitsu, and Wrestling.
It's getting there with the current MMA but I want to see a day when it's not call "Mixed" Martial Arts...I want to see a solidified hybrid.
Maybe some day.