This userscript adds several options to the sidebar of Close Review:
The options invoke API methods to downvote the question, or to vote to close. Voting to close does not count toward the daily limit of review tasks. However, it advances the queue by automatically clicking Skip button. Downvoting does not advance; thus, one can downvote and then vote to close.
Duplicates, migration and custom close reasons are not included in the options. The descriptions of off-topic reasons are not provided: the script targets experienced users who are expected to remember them.