I just wanted to share my thoughts here on what you can do to help improve the overall look and feel of your blog. Obviously you want your theme and graphics to look good and also unique. There are tons of free themes out there that are used over and over which takes away from the blog. However, if you can not afford to purchase a customized theme there are ways that you can improve it and make it unique. Choose a blog that allows you to change the colors including but not limited to background, bars, icons and more. Also you can often choose the way the theme is setup with ad blocks and side bars being rotated around. Creating good content is a must for your blog. Whether you are blogging about a personal hobby, business or trying promote your products and services you want it to capture your audience. The images and written content that you use should also be unique, alluring and interesting for the audience to look at and read. If you have decided on a whim that you now want to create and own a blog the best advice that I can give you is to choose a topic that you know or at least interested in so you don't lose interest or focus just a short time down the road. Blogging isn't easy and its not for everyone. However, if you are one of those who can write, design or at least looking for a new project then it may be for you.
But after all you forgot about hosting problems and then PR problems... Even the best and the most successful blogs have those problems. Even if you give unique and catchy content, your design is perfect... You should pay much time for the blog's promotion and for choosing good hosting (for which you have to pay, as a rule).... Those were some problems of a successful blog
After Google Panda updates start from February 2011 the following 3 terms is more important. 1. Speed of blog 2. Content quality 3. Design
I totally agree with everything you've said. All of that is important - and also, the most important thing in my opinion, is have a strategy and a plan of action, have a daily task list, and stick to it. Make process maps of all your blogging actiivities, and find out which areas you can systemize and automate, and thus improve. Leaving you with more room to grow your blog as a business.
Content, Submit Feed to anywhere and everywhere possible, get guest bloggers to write a blog (attracting their followers), submit to blog directories, social bookmarking.