So is it easier to code your own design? Of course it is. I stepped in to the world of design some 15 years ago and in to coding a little bit later. Since i do both things I can really tell the difference between coding of my own design and coding the client’s design.
While I am laying down the design in Photoshop I am already thinking of the code that should be applied to achieve that specific layout. It’s true that any layout, well almost any layout, can be coded but not without jumping trough hoops though.
The other thing is trying to stay up to date with the latest standards and practice of the web. Nowadays its common to use svg format for logos and icons if not using web fonts like fontawesome and such. It’s really a great solution for retinas and applying some cool animations. But client comes with his own PSD that contains only raster images and expects responsive crispy design anyway. Fonts are another issue and often their usage is not planned well so I have to come up with some alternatives.
Another thing that I’d like to point out is the use of textures. Textures are great and can be used well as section’s backgrounds but here is the cache. Textures need to be seamless and need to tile well. Using a big image as texture is not efficient and can cause loading speed problems.
I plan all things ahead and actively think about all of this issues during the designing process. So when it comes to coding stage of the project everything goes much smoother.
Nevertheless I except both types of projects and try to do my best in getting the optimal results with what I have available.