As I've been looking this over I had to ask myself this:
How long with Leane, Moiraine and Siuan (assuming she had lived) live?
All are considerably weaker than their original potential, but the Companion makes a very clear statement regarding Vandene:
Will Leane and Moiraine live to their original lifespans as dictated by their original OP strength even though they are both now significantly weaker in the Power?
I'd say Leane would still be governed by her original Potential. Her problem seems to be that her physical access to the Power isn't fully restored rather than her ability itself being atrophied, kind of makes me wonder if Flinn or a linked man/woman could restore her full access.
Moiraine, I suspect will not live to her original age limits because the 'Finns seemed to have actually "eaten" her ability altogether. Thus lowering her actual Potential from 13 to 66
Thoughts?