One of the annoyances some found with Gmail has finally been resolved, or at least will be very shortly. Their "What's New" page now includes a blurb about a new "feature" slated to make an appearance -- a delete button.
This new button will be located directly to the left of the dropdown which contains the delete item. To delete a message currently, you need to select the message to delete, open the dropdown, then click "delete". Once this feature is live you will able to select the messages and click "delete" in one less step -- more convenient.
On the topic of making Gmail better, I would really like to see in Gmail use the correct "from" address when an email is sent to a secondary account. For example, when someone sends me an email to email@example.com (which is forwarded to my Gmail) it uses firstname.lastname@example.org as the "from" address when I reply to it -- clearly not what should happen. What bugs you about Gmail? Does anything else need to be added or fixed before the service is taken out of beta?