1. A system for evaluating a plurality of candidate electrostimulation vectors for use in therapeutic stimulation of a heart, the system comprising: a programmable electrostimulator circuit, powered by a battery, configured to deliver electrostimulation to at least one site of the heart using a specified electrostimulation vector; a physiologic sensor circuit configured to sense one or more physiologic signals; a processor circuit, configured to compute a composite efficacy score using at least two cardiac electrical or mechanical signal metrics generated from the sensed one or more physiologic signals, and to generate at least (1) a cardiac stimulation efficacy indicator using the computed composite stimulation efficiency score and (2) a battery longevity indicator, the cardiac stimulation efficacy indicator including a numerical or categorical value indicating a therapeutic effect of the electrostimulation of the heart using the specified electrostimulation vector, the battery longevity indicator including a numerical or categorical value indicating a battery status when the programmable electrostimulator circuit operates according to the specified electrostimulation vector; an electrostimulation vector assessment circuit, included in or communicatively coupled to the processor circuit, configured to: for the plurality of candidate electrostimulation vectors, receive respective cardiac stimulation efficacy indicators and respective battery longevity indicators; and produce a rankable set of at least some of the plurality of candidate electrostimulation vectors, the rankable set operatively rankable according to the respective cardiac stimulation efficacy indicators and the respective battery longevity indicators.