Hi Anil,
I don't really have an opinion on the housekeeper settings, but then I don't do that much tuning work. Having said that, I realized that I do have another observation on the sysmon output, though it doesn't have anything to do with the Unpins:
Engine Busy Utilization CPU Busy I/O Busy Idle
------------------------ -------- -------- --------
Engine 0 2.4 % 83.5 % 14.1 %
Engine 1 0.0 % 0.0 % 100.0 %
Engine 2 0.3 % 79.3 % 20.4 %
Engine 3 0.0 % 0.0 % 100.0 %
------------------------ -------- -------- --------
Two of your 4 engines are idle. I'd noted earlier that no worker processes were being used. I'm wondering if you might not be able to get better performance by having the create index operations make more use of worker processes.
-bret