Last instance - Insert Row - Continue formulas Project

Hello all, I have an ambitious idea I would like to create. We have a gigantic list of parts I've consolidated into a "Master Item List" I would like to make it easy for the users to add new items. Items are grouped by category.

A User's natural thought being:
"I want to add a new [category] item"
The user would then scroll down a huge list to find the category (or autofilter)
Then they'd need to insert a new row by copying the previous one (so that formulas continue)
Then change the contents of the cells that don't have formulas.

I'd like for:
User to select a category from a drop down.
The sheet "autoscrolls" to last instance of that category item.
Automatically inserts a row with continued formulas and conditional formatting, but not the previous rows non-formula content (manually entered values)

If you could help with any part of this project I would greatly appreciate it. Even if it is just one small part of a task I'm looking to use.

Attached an extremely condensed example.