well, in the long run you'll get <7% more from proportional, that's what you can expect.
no need to take your hashrate or any imaginary numbers into account.
I would say not true for those with lower hashrates, but could be wrong.
Should be true for anyone.
Then I stand corrected.
Was thinking the chance to miss blocks with lower hash rates might make a difference.
If you miss each one of two rounds, then you need ~twice more hashrate. Then you will have, possibly, one share in each round, which gives you twice the reward, just proportional to your speed.