Charles, flower buds that drop are usually male flowers (no ovaries). I've had some varieties appear to be much more precocious than others, especially Azadi, while others are on the other end (Sin Pepe was slow to start growing and set few fruits until five years old).
There is no easy way to tell when a pomegranate is ripe. I picked up a tip from a Persian last year (my doctor), he pressed against the rind to check to see how easily he could pop a kernel. I haven't given that much of a try myself yet. My poms ripen after weather turns cooler and I've heard from Richard Ashton in Texas that rinds quit growing after nighttime temperatures drop below a certain level (maybe 45F?). In any event, noticing fruits become less round and having a bit more of ridges seems to indicate kernels have sized up and may be ripe. If this continues, the fruit will burst as it's method of naturally reproducing. I also see most varieties seem to have a rind that becomes less shiny and more dull as they become ripe. The only sure method is to do some taste testing. I end up with many discarded fruits in my orchard from this process.