By default, Blogger comments are very simple with a profile picture but I'll tell you a simple way to make your comments look stylish, beautiful & completely customizable.
Blogspot How To: How to Restore Pencil to Edit Posts
When you're logged in to your Blogger account and you see your own blog, you might have noticed a small pencil in your post footer. This pencil lets you easily edit any post right from your blog but if you're using a custom template or for some other reason, you can't see this small tool then you can easily restore or recover it.
Blogspot Tutorial: Add a Cool Animated Favicon in Blogger
What is a favicon?
A favicon (short for favorites icon), also known as a website icon, shortcut icon, url icon, or bookmark icon is a 16x16 (or 32x32) pixel square icon associated with a particular website or webpage. (Wikipedia.Org)