My attitude re names these days fluctates between the-name-is-everything and back to sanity.
A week ago I was obsessed with the domain name WordPrice.com which a friendly cybersquatter wanted to sell me for $700. I even contacted the owner of a very similar mark and kindly got the OK to use it for what I intended. Then backed off at the last minute because a) I refuse to support cybersquatting and b) names are more about creating a well loved and well remembered brand than pretty words.
Keep in mind the relative strength of different types of trademarks when you’re thinking about future brands. Make sure you do a USPTO search and at some point spend $500 with a TM attorney to get your use of your new mark on record and start the trademark clock. I also tend to screenshot a few 100-result google searches for any new potentially strong mark I’m going to use. I date them and file them. [Once you've had your ass handed to you in a trademark lawsuit like I have, you get paranoid]