I want to create a level 2 wererat archer for an upcoming adventure, and I see two options. I'm curious as to everyone's opinions on these two options and which one I should use. I like the flavor of the elf archer's Archer's Mobility and Not so Close abilities because they seem to fit the flavor of a wererat artillery - scurrying around to get a better shot and out of the way of larger opponents.
1. Build from Scratch: Use the DMG rules for building an artillery monster and just give it the Archer's Mobility and Not so Close abilities along with the wererat's Bite and Shapeshift.
2. Transform: Use the elf archer as written, but get rid of Elven Accuracy and Mobility and add Bite and Shapeshift.
Is there even a difference, or will both routes basically lead me to the same destination?
Just as a note, there isn't a substantial elf population in the campaign, so I'd prefer not to just use the elf archer as an elf with the lycanthrope abilities on top of it.
Bonus Question: Any suggestions for an elite ability for a wererat archer?