4. If the suicide ganker is even yellow-boxed by a member of the victim corp, the suicide ganker can defend as he was operating under a war dec with the victim corp.

Well, I do know that the killrights are for me and me alone to utilize, certainly not my entire corp.
Further, it is pretty pointless for an industrial alt to have kill rights, since the vast majority of indy alts don't have the skills to seek retribution. But a corp, that is another matter.

Let's put it this way, either you underestimate the amount of indy pilots that have compentent PvP alts or corp mates, or I am overestimating the combat capabilities of most industrial corps.

One way, you get more PvP which you guys profess to love so much, other way, nothing changes and this proposed change does not affect you. Seems like a no-lose situation for suicide gankers.

Now you are being obtuse. The existing kill rights mechanism works on an individual level, and is inadequate for the vast majority of indy alts to seek retribution.

Fair enough. Let me paraphrase to make sure I am understanding what you are saying:
Under the current game mechanics, if the suicide ganker is attacked by a past indy victim, say with minimal skills (but has to have the ability to fit a scram/disrupter to get the initial tackle), the indy victim's corp buddies can keep on RR'ing the indy victim with no chance of the suicide ganker shooting the RR corp buddies?

And even if it did, the suicide ganker would be able to burn back to a gate and jump long before the industrial with the poor PvP skills could bring down the suicide ganker's ship. Somehow, I think some indy alt with say L2 in medium autocannons and BC III, in a Cane against a Tornado, not much chance of bringing down the Tornado.

The overall problem with the proposal is that it assumes the gankers have any interest in their gank alt. Or that blowing up said alt would do anything to ruin their day. Which is of course preposterous. I've been ganked once. Got careless moving 40M or so out of Jita. Checked the KRs for that toon and saw that I had rights on a character maybe a couple weeks old (told you, careless. transpo in an unfit frig.). I mean it can't fly anything worth killing. If it could I would have been docked with a locator fitting a PvP ship. As it is he likely transferred anything of value to another toon and has stopped any training on the gank alt some time ago now. This is the real problem with the mechanic. There is really no risk on the ganker's end. And extended kill rights would not create any.

Who?
New players who read about ganking and dive right in (again not capable of flying anything worth killing)?
Low and Null seccers jumping on the goonwagon for lulz? Again not flying (or wearing implants) that are worth a damn?
Naturally the aggressions mechanics are different for low sec. That is why it is low sec.
I realize here that you are trying to defend a manner of play you deem 'fun'. I have not denied that or suggested any change in aggression or other game mechanics to combat it (if anything I was arguing against a change in mechanics). The fact remains that the bulk of hi sec ganks are gank-alts. And that there is little point in using KRs on a gank alt. It has been that way for years.