Nah. The battery monitor dissipates a negligible amount of power, in the tens of milliwatts. While the ham-fisted design of the flasher probably burns more power than it should with transistor base currents, that portion of the circuit doesn't generate any perceptible heat either. The real concern I had was the heat dissipated in the flasher's driver transistors (Q2 and Q3), but those fellows are rated pretty high for their small size -- 5A continuous collector current, and 750mW heat dissipation -- while the loads on them are pretty light (~150mA for Q2, ~250mA for Q3). Overall, I'm not worried. *touches wood*

-JAB