some folks learn quickly - change vacation so that for every day they are on vacation you have to wait before you can vacation again
like if I was on vacation 10 days, I come off and attack, attack, attack and then not be able to vacation again for a week (week being max)
that stops folks from living on vacation, attacking and jumping right back on vacation
protection - stinks to high heaven but it sales kawas and fox $ from some players, just sure they cannot attack from a protected base