[Edi]

Bean Sidhe are recruitable anywhere and they are far more versatile than the mermage, if you want a comparison.

Bean Sidhe can provide full site searching for Air, Water and Nature, they can forge a fair few combo items that are hard to come by elsewhere and ultimately build all water boosters, have glamour and exceptional stealth and forest movement. Further, depending on what randoms they get, they can function as battle mages. She also does not get power reduction like the mermage does on land.

Yes, the indie enchantress is far better. She is also only recruitable from sites you need to be lucky enough to find first and generally kicks almost any national mage's arse in a cost comparison analysis.

The whole goddamn point in comparisons is compare nations against each other as a whole, not just snip out some arbitrary unit and then compare those.