Workflow holidays: request validation

When a employee has a Holiday Leave Request. The other employees / users who have to approve that request do not receive any kind of information. The ideal would be that a Request appears in the top-right Request Icon, or some message inform about this holiday request.

And there is a related feature that makes this (approved holiday request) more complicated, this features is when a user goes to Human Resource module, clicks on Holidays and Allocation Requests, this window just shows the allocation request for that user, and the user has to click on "My Leaves" button (between Employee and Department search boxes) to see the other allocation requests.

How can we modify the workflow holidays to make appears the leaves request in the Request button (top-right)? And how can we modify the workflow holidays to change the user who has to validate the leaves?

Thanks in advance.
Daniel.