Multi-hop based Wireless sensor network (WSN) has gained significant importance catering to large scale application demands and integrated with Internet of Things (IoT) in recent times. Conventional WSN faces hotspot problem, since nodes in the one-hop neighbourhood of static sink faces battery depletion rapidly for relaying other nodes' traffic. Mobile sink based approaches suffer from excessive control overhead in terms of topology updates, route computation and maintenance by sensor nodes. This work proposes a novel quasi-mobile sink query driven model to optimize cost factors such as deployment, energy and routing for large scale soft real-time applications. A corona based beacon-less flexible tree routing is adopted. In this model, sink moves in a predefined pattern covering the deployment zone but remains stationary for a configurable sojourn time during the query dissemination and data gathering phase. It is inferred from simulation results that significant energy savings is achieved over the hotspot region near the sink, with increase in traffic rate compared to static sink solution. High data delivery ratio and energy efficiency is achieved with increase in network size in comparison with existing sink mobility models. Empirical range test measurements of average Received Signal Strength Indicator (RSSI), Packet Success Rate (PSR) are also performed to determine the optimal transmission power level and ensure proper deployment for effective coverage and network connectivity. © 2019, International Journal of Intelligent Engineering and Systems.