- I'm currently doing a job of designing a website.
I think this implies more professionnality by using a word 'job'. this sentence would never imply that I'm at the moment designing a website sitting on a chair and using computer. Rather, It would imply that designing a website is what I spend most of my time at these days.
- I'm currently designing a website.
this could imply that I'm currently in front of computer designing a website.
So, when I describe what I usually do these days, I would say #1. Am I right?