我是否可以进一步优化此PHP脚本以从MySQL数据库生成动态导航？

I'm working on a new CMS to use on repeative projects. Basically this chunk of code connects to a server, grabs all the names of the tables and uses them to generate a simple navigation. It works pretty great for what I need however I'm just wondering if maybe I can optimize this code sniplet even more and make it even more simple. Maybe making a class that could customize the formating? Etc. I tried to make this as "bare-bones" as possible. I'm working on a new CMS to use on repeative pr