Dryden and Orr and Bossy all had short careers as well.
Their accomplishments are better, but their career lengths never get talked about in terms of hurting where they are on all time lists. The short career lengths probably help them more than hurt them.
There are lots of guys in the Hall of Fame that never won and individual awards, and were never in any top ten discussions.
7 years and the individual accomplishments Thomas has should be enough to get him into the Hall. When you have guys like Cheevers, Duff, Lowe, Gillies, and others of that ilk in the Hall, its insane that Thomas isn't there.