I post here a simple excel spreadsheet I have been working on. Basically, by entering your level and statistics, it automatically calculates your damage mitigation. Furthermore, you may input new stat changes you want to add and it will calculate the difference in damage mitigation. There are a few "ways" of calculating this mitigation included. Obviously, most of it is made for melee damage only; the "Maximum Health" - giving the highest burst damage you can sustain - is for melee, as is your "Health Left" - which gives the health you have left after a fight of a determined length during which you take a certain amount of damage; any negative value has to be healed.
I used it personally to check which virtues were the best, but you can make any use of it.
One last thing: If you find it helpful and have some silvers to spare, I am trying to get money for my Deluxe House, so any donation would be welcome. My character name is Gorthamer, on Imladris. (Obviously.)
If there is any problem with the link, let me know.