Focus 1.6tdci potential?

Hi guys. 

Been lurking for a bit so here is my first real post following my introduction a short while back. 

I have a 2010 1.6 tdci. Couldn't tell you much else about it in all honesty.

I'm hoping to hang on to it for a year or two and was thinking what I could do to improve it. 

It's ex police so has a few dents and scratches here and there. Recently my clumbsy neighbor scratched the rear bumper quite bad as well  figure I've always wanted an st or zetec s maybe I could look at kits? New bumpers etc. 

Is it worth even considering this type of modification? Considering they will need spraying as well and it's unlikely I could do all the work myself. Unless it's easy. 

Then on to engine mods. I've heard remapping can do quite a bit but surely this would be pushing the car beyond what it was designed for. Maybe it's better to just save for a model with a larger engine or even get a mk3 focus? 

Thanks guys. Sorry for such a long post.

Edit. Open to other suggestions. I've heard about a k&n filter and maybe getting alloys. 

Tldr

Is it worth modding my 1.6 to be prettier and faster or do people feel I should just save for a better/newer model. Plan on keeping the car for 1 to 2 years.