If we force the interface with 30 sec of interval instead of default 5 mins, will it be helpful for the traffic, it being more granular.Also, would it also help me in QOS as the packets would be tagged within 30 sec interval rather than long 5 mins.
Unclear what you consider a "better drive".
No, nothing comes to mind where changing the interface's load interval would have any impact with QoS.
There are other timers that can change how QoS behaves. Policer or shaper Tc interval comes to mind. WRED decay values also depend on time (although unclear how its parameters relate to absolute "clock" times).
QoS often most impacted by queuing methology, queue depths, and how packets dropped, that don't depend on a timer.
What do you think your issue is, or what are you trying to accomplish?