You want to use either the
Ramp Sequence or the
Ramp Load Generator. To find out whether the machine running LoadUI or the server is the bottleneck, please see
Find the bottleneck. If the machine running LoadUI is the bottleneck, you need to distribute your tests using agents.
You can change the max queue size in the SoapUI Runner settings; but most of the times, this is not what you want to do (the queue will often fill up regardless of its size -- because you have one of the bottlenecks mentioned above).
Regards
Henrik
LoadUI team