We theoretically investigate strategies for harnessing quantum interference to optimize the figure of merit $ZT$, power output, and thermodynamic efficiency in multi-quantum-dot Aharonov-Bohm thermoelectric heat engines. Within the nonequilibrium Green's function formalism, we demonstrate that interference effects, such as Fano-type asymmetries, Dicke-like superradiant and subradiant modes, and multipeaked transmission spectra, can be tailored through device geometry, magnetic flux, and dot-lead coupling to produce hybrid transmission profiles that combine features of Lorentzian, boxcar, and Fano line shapes. Such engineered profiles enable configurations that balance the high efficiency of sharp Lorentzian resonances with the high power output of boxcarlike spectra, achieving near-optimal power-efficiency trade-offs. For symmetric quantum-dot arrays in square, pentagonal, and hexagonal configurations, we identify an optimal coupling regime, $t/\gamma \simeq 2$ (with interdot tunneling amplitude $t$ and dot-lead coupling strength $\gamma$), which yields the most favorable trade-off between power and efficiency. In particular, a hexagonal six-dot configuration achieves a $ZT\sim 30$ at dilution temperatures, while the four-dot geometry reaches $\sim 76\%$ of Carnot efficiency with output power $4.74fW$. We further find a direct correspondence between the high-$ZT$ regime and the maximal violation of the Wiedemann-Franz law. Introducing coupling asymmetry between source and drain enhances both efficiency and power. Scaling analysis reveals that efficiency increases systematically with the number of quantum dots, whereas power output reaches its maximum at intermediate system sizes. These results establish coherent control in multidot nanostructures as a viable pathway toward high-performance quantum thermoelectric heat engines, particularly relevant for ultralow-power electronics applications.

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• Aharonov-Bohm effect
• Mesoscopics
• Quantum interference effects
• Quantum transport
• Thermoelectric effects
• Quantum dots
• Green's function methods
• Landauer formula