The differences between styles is going to be (for the most part) cosmetic. If we're talking about simple self-defense, or as an exercise regimen, there's little that would distinguish the ass-kicking you can dish out as a practitioner of Shotokan from the ass-kicking you can dish out as a practitioner of Krav Maga, Muay Thai, BJJ, or anything else.
It depends on what you enjoy doing. Krav Maga (which is based on Aikido, which has the same origin in Shoto-Ryu as Judo and Karate) is very focused on grappling. Lots of locks, lots of submission moves. Shotokan is based in striking (mostly with the hands), and Tae Kwon Do is based on striking (mostly with the feet). Interesting, the major distinction is between gaining power from ones hips (in a side-to-side motion, sort of) and gaining power from ones legs (in an up-and-down motion, sort of). The actual kata of TKD and Shotokan are surprisingly similar.
But, unless you're planning on getting in a lot of fights, or fights with people who've trained in a martial art themselves, it's kind of six of one, half-dozen for the other. But, even then, an equally-skilled practitioner of any style will be able to hold his own against any other style.
It depends on what you enjoy doing. Krav Maga (which is based on Aikido, which has the same origin in Shoto-Ryu as Judo and Karate) is very focused on grappling. Lots of locks, lots of submission moves. Shotokan is based in striking (mostly with the hands), and Tae Kwon Do is based on striking (mostly with the feet). Interesting, the major distinction is between gaining power from ones hips (in a side-to-side motion, sort of) and gaining power from ones legs (in an up-and-down motion, sort of). The actual kata of TKD and Shotokan are surprisingly similar.
But, unless you're planning on getting in a lot of fights, or fights with people who've trained in a martial art themselves, it's kind of six of one, half-dozen for the other. But, even then, an equally-skilled practitioner of any style will be able to hold his own against any other style.