All 7 of those people now have a 7 v 1 in their gank rating.
The gank penalty impacts everyone, not just bards. A warrior with a GOM with 2.5 will likely not find openings for skills when ganging more often than a warrior with a 1.5 GOM.

There has always been a flaw in group battles as it relates to GOM in that the size of Grembolin's group is never displayed or considered.
It also disregards facts such as when you die in an unrelated encounter that takes place before your adrenaline wears off from the initial.

I don't think the GOM is accurate, or that it should be tied to any mechanical functions of the game because of it's failures as it relates to cabal raids (I'd say this is the majority of group on group fights).

Gank protection can be a static thing and how often you have ganged should have no impact on ability to gang. Honestly, someone that has ganged a lot would be better at it, not worse.

Basically I'd like it to work out that you're unlikely to be hit by 2 commands against you from 2 sources, but will be hit at a rate higher than 1.
2 v 1 Commands have 90% success rate
3 v 1 Commands have 60% success rate
4 v 1 Commands have 40% success rate
anything greater have 20% success rate.
Number of melee attacks should equally diminish.