Hi,
Flash of RUT240 should be able to go through 100,000 (100k) cycles of erasing and read is unlimited.
So if we won't look at the accurate numbers (as these are not really accurate when there are hundreds of services running and doing the same thing with your flash and that's excluding uci commit and eventslog that you've mentionted), your flash should be alright as long as you're not trying to push something big, that could fill up your whole flash in one go, back and forth each day, each hour and so on.
EB.