I just read something similar to this. I can only advice to use the SlackBuilds in order to build better packages (and control your home-made packages). You will need, obviously, to modify some small things in them to fit your needs (like apache2 instead of apache inside the php SlackBuild).
The best way to mess with the Source is the Master's way. This means Pat Volkerding's way. I try to follow it.
May the Source be with you!