Adapting the squawk would be an obvious mod
I've for some time wondered how straightforward it would be to have a transponder automatically squawk something from the 7000 series when an RA is triggered.
And whether this would in fact be a good (at least short term) solution, or if it would present more problems.
Sometimes simple is best.
I suspect that getting everyone to consider and agree to such an idea might be a larger hurdle than the tech aspects.