Write with conviction. Pick a side and be bold. And if you're wrong, admit it.
E-commerce bloggers can gradually choose to write curated content from other websites/blogs. That always helps because a buyer will generally not spend much time surfing. He/she will appreciate it if you provide most of what they are looking for.
Blogging is a must for artists, a great way to display your work, connect with your prospective buyers and collectors!