I'm of the opinion that we should avoid kicking most (if not all) people until we have a real reason to (A limit on members, generally being mean, exc) for the reason that as a player who jumps to/from MMORPG's, sometimes years at a time before returning, it's nice to be able to come back and be welcomed back, without that often people will just lose all interest to play.
We should focus on growth of the guild's active member pool first, before kicking anyone. Get out there, do events, bring people in, meet new people - because if you kick all the inactives, it's not going to make a bit of difference to the activity levels of the guild overall, infact it'll just make it feel MORE lonely to those who are still in the guild, as there will be *no chance* of anyone logging on and chatting/playing the game/exc.
Once the guild is active, and flourishing with active players, then it is the time to kick people. But not now. People going inactive can be for many reasons, almost none of them are because of the guild - From real life issues, to simply not enjoying the game anymore, having problems with the way the game is handled, and so on.
If we must kick people, make sure to send them an in-game message saying they are welcome back at any time should they come back, and making clear they're welcome. But I would advise against this simply because it will just make the guild feel even more empty.
Just my thoughts