Thanks. The philosophy behind the proposed algorithms is not about stopping anybody doing what they want, but about limiting their effect on the whole ecosystem when that becomes excessive. Now, "excessive" is not defined by a fixed demarcation, but you can see that the rewards can drop off fairly sharply. I think that the "income" even with N-20% is still very good. Also, these would be on top of the current N-2% rule for each upvote.
Your point about self-voting on comments: there is also a good argument that as such voting is to achieve a benefit - to bump up the comment - then it should incur a small fee rather than a reward! But that is not in the current model.
Also, as a coder, you may wish to comment on the speed and efficiency of the algorithms, so as not to slow down the creation of blocks. This is one aspect that some people do not consider when they come up with a lot of different conditionals trying to cover every possible angle.
The overall aim is to shift the balance away from sub-optimal self-voting (in all its forms) and towards the more social behaviour that is more efficient for the whole ecosystem.