Power consumption of DRAM is high, what are you talking about? DRAM requires constant refresh -- the whole reason DRAM can be high-density if because it is a 1-T cell with a trench capacitor -- but the capacitor needs to be refreshed on a synchronized basis (hence SDRAM) -- that was the big innovation.
And yes, array size affects latency but so does the underlying process technology (much more so across technologies).
And yes, array size affects latency but so does the underlying process technology (much more so across technologies).