as you have "last seen", a user could join a channel and stay for days on end...
adding a part event and maybe even a quit event, would give a more accurate "last seen" time...

you could also use $prop and use one alias...

this is a quick example, untested...

menu * { 
  savednicks
  .savenick: $ohn($$1).1
  .delnick: $ohn($$1).2
  .seeinfo: $ohn($$1).3
  .search: $ohn
}
alias ohn { 
  if ($prop = 1) { 
    var %ohnevent = $iif($event = join,joining $chan, $iif($event = nick,changing nick to $newnick,leaving the server))
    writeini -n savednick.ini $1 ip $address($1,2) last seen %ohnevent on $fulldate 
  }
  elseif ($prop = 2) { remini -n savednick.ini $1 }
  elseif ($prop = 3) { echo -a ---> $readini(savednick.ini, $1,$address($1,2)) <--- }
  else {
    var %nick $$?="searching for who?"
    echo -a ---> $readini(savednicks.ini, %nick, ip) <---
  }
}
on *:JOIN:#: { $ohn($nick).1 }
on *:PART:#: { $ohn($nick).1 }
on *:QUIT: { $ohn($nick).1 }