The filter options should be consistent with the designs in &454.
This iteration will not have weights in Starter+, since the current implementation doesn't have weights. We have a separate iteration (https://gitlab.com/gitlab-org/gitlab-ee/issues/7928) to add the weight filter.
When you load the page, the assignee filter is pre-selected to yourself, as shown in the screenshot below. (This is consistent with the current design due to performance issues of loading everything if no filter is selected.
If you attempt to have no filters entered, you will get a message, again consistent with the current implementation.