I did a little bit of testing of the Shishi, and think they do seem a little bit OP for just 30A gems a pair. Not massively OP by any means, but maybe just enough so that it can be noticed
Since a magic phase raiding thug that's good to go out of the box for 15A seems a little bit cheap to me. Especially as other good magic phase raiders in the game need a bit more investment (even Sidhe Lords tend to need at least a 10gem shield and 5gem weapon. And a good bless as well to raid effectively). Not even Golems (the other general go-to magic phase raider) can raid without equipment. And they cost 30 Astral.
I think either the cost should be upped to 40A for the pair (as others have suggested), or de-buff them a bit. Perhaps remove the quickness (goes against the description though), or just knock a few points off protection (3-5). Again as some have suggested.
Or, maybe think about removing the magic paths altogether and reducing the cost to 20A for the pair. Think they'd still have a use at that price without the magic, as they can still border raid with Lychan amulet and Girdle. Plus still be a great help taking out Thugs or low end SC's (and bonus v evil) due to the six attacks.
For me, the main issue with them right now is that they are good to go out of the box, and you don't have the logistical hassle of needing to change equipment depending on whether you are raiding or taking down Thugs/SC's. As the Shishi's are good to go against either at any time. Which is not the case for most other thugs in the game, as they usually need to be specially equipped depending on what they are going up against.