Hi spindrift,
There is currently no way to set the number of general timeslots displayed. This control is still in a beta stage, however your request seems quite intuitive. I was planning on adding a filter by user as you suggested,, but we could improve the control by adding a filter by dates option, so that you could display the last month's timeslots. We will have to implement pagination on the control also...
So, yes, we are planning on solving these problems. However, I don't know when the solution might be available, probably for the 1.5 release, as we are now closing the 1.4 beta