Some Guilds have high requirements, whether it be to have full 4* or 5*. However sometimes some promising 2* or 3* want to join; but need to wait until they have the requirements.

My suggestion is that there is a separate branch of the guild that is dedicated to these players.

For example: you have a guild called XX, then the branch would be called XX waiting list. In this branch of the guild, guild-masters and officers of XX will have their positions in the new branch of the guild. But the veterans, members, and recruits of the original guild won't be part of this separate branch; instead the officers and guild-masters will invite the 2*s and 3*s into this separate Waiting list part of the guild, and when they reach the requirements the officers and Guild-masters can then place them into the main branch of the guild XX.