It doesn't matter, as long as it's reasonable. The players at these stakes are almost never changing their behavior based on the EXACT SIZE of your river bet. It's the fact that you bet that changes the dynamic.

It's unusual for players to bluff raise at the end. So if you are afraid of being bluffed, just bet. A small number of times you'll be bluff raised; don't worry about it.

Well put.
Thank you.

--cm

Perhaps this concept of "various reads" is being misunderstood by those who have posted responses such as this.

Consider this to be multiple questions in one post.
Villain 1 = Loose aggressive bluffer (one extreme)
Villain 2 = Tight passive (the other extreme)
Villain 3 = Unknown (somewhere in the middle)

By understanding the proper response versus any type of villain, I will be more adept in handling this type of situation whenever it comes up.
If your recommendation varies based on the read, then that is critical information that must be included in your advice.
Unfortunately, many advisors leave this necessary information out.
I encourage those responding to not forget this.

Thanks for taking the time to answer.

--cm