If you truly think everyone in the party did well, say so.

Do you have any idea how nice it is to see a "Thank you for the smooth run" or even just a "{Good Job!}" at the end?
Even better, say something during the run. Say 'well done' after a smooth boss fight', nice tanking', 'good healing', 'dat DPS'.

The commendations are little extra bonus, but if you honestly feel people deserve more recognition, put in the small effort it takes to type. As someone with performance anxiety who has friends with social anxiety, I can promise you... it means a lot.