Yes all those things that you mentioned are done by default. What I'm simply saying is that you have to watch out for the temptation of adding non-critical features or rolling your own solution without doing your hw first. It's easier said than done.

In regards to design, people spend a lot of time creating photoshop mockups, then modeling it with css and html. I'm just saying, if you want to get it done quickly, just skip all that and keep it minimal.