One of the things I like about this idea is that it would encourage people to look for obscure species to record, or get into learning difficult taxa. The effect of that I think would be much more valuable than the detriment of a few gamifiers doing dodgy IDs (You’d probably have to get quite into iNat before you noticed these things anyway, and therefore probably not so irresponsible).
They might take up a bit of space unless they were done as little badges/rosettes of different colours next to the RG banner (hover over to get the explanation). I quite like the idea of having all of the above: ‘First uploaded observation’, ‘first identified observation’, and ‘oldest observation’. All of them should be applicable only to research grade obsevration, and should be redeployed if the truth changes.
In short, I like this idea. Whether the programmers like it… I will leave to them!