Using message stack to replace guestbook module

I currently use guestbook module which is quite actively used. But It is not being actively developed and its future is in question.

I am thinking message stack can replace most of the guestbook functions. But looking for help if someone already done this.

For example I can create a message type as Guestbook Entry/ But then how one does add dynamic text to the entry when it is created? How to show all guest book entries intended for an user etc. Any thoughts/suggestions?