Any real combatives are good. The problem is finding them, since most of the good trainers have gov't or contractor jobs. I don't know enough about krav maga to be able to recommend it. Look around and keep your eyes open.
The real rules of fighting---not "fighting" as in the highly antagonistic and painful game designed to be fairly safe that you see on TV--are to target eyes, groin, nose, neck, and joints. If you see a good krav maga demo you'll watch him break at least one major joint right away after establishing a superior angle while disrupting the opponent's posture, possibly by striking (open-handed) at the face.
Boxing, Judo, Kickboxing, MMA, western sport wrestling, and the like will give you a good foundation and bodily perception to give you an edge.
>condition
>falling for the hit hard bone with your fists meme
Hammer fists, open hand strikes (nose, chin, ear slap if you know how), and fingers in the eyes are the order of the day. Hit hard targets with "soft" things like open hands. Soft targets with hard things like fists.
Example of real combative wrestling (this is a pure demo of the grappling, so no strikes, but heed the rule above):
>youtube.com/watch?v=W0fV1oB3j4c
Unfortunately, this particular book didn't show any of the ground work, which might be because that would be part of a general wrestling curriculum all fighting nobles would know from childhood, whereas the standup combatives are a bit different.
A boxing primer:
>youtube.com/watch?v=hS1VnE7YvMc
If you can get a partner or find a gym that's willing to do it, look at Ned Donnelly's Self Defence, or The Art of Boxing. Although he was fighting when boxing started to take on the rules that make it what it is today, a lot of his stances and technique allow illegal moves to flow out and better counter grappling, making it a good read.
You can also look up Self Defense for Gentlemen and Ladies, by Col. Thomas Hoyer Monstery.