This is a rule I know from a video tutorial:
6. Keep the text togheter, so reduce the space between letters. This is a typography rule. Also, like on the 2nd logo of Avera's 1st post, there has to be some difference between the company name and description (The UK's... etc) The difference there is that the description is in all caps and the name is not. This probably makes the name stand out, and it makes the logo look way better.