I think we place too much emphasis on membership to the unfortunate exclusion of simple fellowship. Too many of us seem to think that only those who are members or "progressing investigators" should be with us as we worship. In my view, although we could create dozens of more narrow categories, we have four general options for attendance in our meetings:
1) "Fully committed members" - holding temple recommends and striving to live every aspect of the Gospel to the best of their ability.
2) "Partially committed members" - sporadic or regular attendees (often not holding temple recommends) struggling or unable to live some basic standards expected of fully committed members
3) "Progressing investigators" - people who are serious about their efforts to decide on future membership and exhibit that commitment by attending church regularly and meeting basic expectations of membership
4) "Committed non-members" - those who want to worship with us but have no intention of becoming "members in good standing and future temple recommend holders".
I see this final category as the ultimate test of our acceptance of the true Gospel of Jesus Christ. I wish we were willing to love and worship with anyone who is willing to be with us and let them work out their own issues as we strive to work out ours. In a nutshell, I wish we could separate fellowship from membership - and fellowship everyone.
How willing are we to accept a habitual drunk as our pew mate? How willing are we to embrace a homosexual couple in our meetings - understanding that they will hear the Law of Chastity preached in our meetings and might never be baptized and join our membership ranks? How willing are we to tolerate the smell of tobacco from the pew in front of us? How willing are we to have a Baptist or a Methodist or a Catholic or a Jew or a Muslim worship at our side if they are open about their unwillingness to be baptized? How willing are we, sinners in our own way, to worship alongside sinners in a different way - understanding that they might never enter category #1, but willing to love and serve them even as they remain in category #4?