1. it does. because having say 1k txsigops and 80k blocksigops vs 4k(mathematically twisted to be treated as 16k) means you cannot use up all the blocksigops with 5-7tx's but instead need 80+ tx's if your malicious
also
That is nonsensical. It does not allow for more throughput. All it does is make it a little bit harder to abuse sigops to fill up blocks.
ask yourself why should anyone have the ability to make 1tx that uses up 14%-20% of a blocks limit.
They may be use cases which require this. Who are you to censor such transactions?
2) quadratics of 4k of a few seconds vs 1k thats only a few milliseconds per tx..
Irrelevant. It is still quadratic validation time.
a HOPE of priority of segwit users
No. It is going to happen as long as there are reasonable pools/miners, which we know that there are (e.g. Bitfury).