While the queue is being dominated by at most 2 people, of course it doesn't make sense. Given that they get queued just as much as a top 19 witness, I'd say logically they should be given the same pay - effectively 1/25th.
However, let's assume the move to Equihash happens, and open source Equihash miners catch up to closed ones. (which should happen given the amount of attention Zcash has received - I notice Claymore has boosted hashrates by nearly 2x in a week.)
Would someone investing a ton of computational power into mining not deserve a high reward? If someone goes out and buys 100 GPUs to dominate the mining queue, I believe there's an argument to be made for the objective contribution. But that seems some ways off and a lot of assumptions at this stage...
I forgot to address the Equihash proposal, I just put an addendum at the bottom of the post.