Which router do you use? I've been considering this solution for a while. It seems inconvenient, but I might get used to it to avoid this fuckery.
I keep forgetting it's on in my bag when I come home, then it's dead when I go to leave the house again. Fortunately I have a USB outlet in my car; I don't keep SIM cards in any other devices now (other than my dumbphone for SMS).