A doubler goes on the eyepiece end of the binocular.
Looking through high magnification binoculars does not look anything like seeing through a drinking straw, UNLESS, you have a binocular with too little eye relief, or, you are looking through an inexpensive zoom binocular.
Yes, higher magnification binoculars have a smaller field of view, BUT, because you are using both eyes, the viewing can be, and is, very rewarding. Often times it depends on your subject. The smaller the object you are viewing the more detail you can see, with higher magnification.
I use binoculars all the way from 7x to 30x, and it is alot of fun and enjoyment. Obviously, the higher the magnification, the greater the level of support you will need, similar to a telephoto lens on a 35mm camera.