Sometimes I find users with wanted coins but with no swaps, only old swaps, or only a few coins in swap list. I write a message with a swap offer but really I do not know if this user is active or not, and if he/she can read my message or not... Because of not all user check the option I don't want to exchange at all for the moment in user account settings.
Can be useful to show the date of last login in user profile. For example, if a user last login was more than one year ago we can suppose this user is inactive and do not search in her/his swap list.
I do not say the user status be changed to active/inactive by system according to date of last login. System show the date of last login and then we can decide if try or not a swap.