I routinely write in English, Spanish, French, and Finnish, and I code several hours a day. For me, the best layout (other than my Dactyl Manuform's, which is l

I routinely write in English, Spanish, French, and Finnish, and I code several hours a day. For me, the best layout (other than my Dactyl Manuform's, which is layered) is the standard ANSI US, with a compose key. The compose key gives me easy access to all diacriticals and accents, and I don't need to switch contexts at all.