Yeah I think I got it!

For others, I got a 1070 GTX, getting around 470 Sol/s equihash. That's 0.47 KSol/s, which at the current rate of around 1.90 would yield 0.893 mBTC/day.
In comparison, I'm now mining sib, at a rate of around 9 MH/s which at the current rate of 0.18 would yield 3.24 mBTC/day, so yeah, much more profitable!

Everything makes sense now!
Disabling equihash in the miner actually just saves time in the rotation, since you know that's it's never gonna be selected (for now).

Yeah thanks!