What makes a good Industry Score™ is relative, because it depends on your personal goals as a writer, and it depends on the scores of other similar projects (which share the same genre and/or format). However, it is worth noting that over 50% of all projects have an Industry Score that is below 150 and scripts with a score of 300 and above frequently earn a spot on The Red List. Very, very few projects earn a score higher than 500.
An Industry Score™ that puts your script on the Red List is providing extra exposure, but just because your script isn't yet on the Red List doesn't at all mean that your Industry Score™ isn't good or won't help get exposure on your script. Industry members search for very specific scripts and don't always use the Red List. To have any Industry Score at all it means you've had a positive read or contest placement, so a "low" Industry Score is still a positive.
It's important to note that Industry Score™ is not a metric of quality, it's a metric of confidence of quality, which increases with more strong evaluations. Any Industry Score™ at all is a positive. If your score is less than 100, it doesn't mean that the script isn't excellent, it means that it's received some praise and we're just not sure how good it is yet.
Take a look at this chart of Coverfly-qualifying competitions.
Finally, we don't encourage writers to enter contest just to increase their Industry Score™. Enter the contests you otherwise would and use your Industry Score™ as an extra too to gain exposure on your script.