Hmm, so the Muramasa casts Drain... and seemed to recover 90 HP, this was against an enemy with strong Magical Defense mind you, but by the time you get the Muramasa that's all there is. Against a foe with very little Magic Defense it recovers about 590 which I assume was the general amount you were going for.
Also what is being mentioned on the Romhacking topic... oh how i would love to be able to display "Strong Against X, Effective Against X Status Protection X,Y,Z but the status menu is abit chock full. Here are the options for the Status Menu that can be gotten rid of...
Class/Handedness/HP/MP (because it's already right there...) and the word Ability (which never made sense really)
The issue would be that we would need new small text graphics for the elements and the statuses.
The easiest option is to do what I did for Combat Boost and what Grond's FFI used, just have a text file with all of the stat boosts, resistances, weapon elements, and racial effectiveness. I'd be willing to cook one up for you after this playthrough actually.
I am finished with everything on the Overworld and am just about to head to the Moon.

Well, I did visit Bahamut with Rydia and as you mentioned there is a bit extra there. A cute little reference. I'm not sure what Bahamut is referring to though when he says that Rydia is not the last of the Summoners though.
Also Kain is still nowhere to be found and Bahamut still says "T" when you go to revisit him.