I agree with you on these parts. I think a min 1 abduct is too blunt to try to fix it, but I would like to see the risk / reward of running land def adjusted.
Yes, both KDs would be doing it but to different provs (ie KD wide the gains would net off, but on a province basis they wouldn't). Some provs gain, some would lose. I can see an argument that that isn't a bad outcome for other reasons (that it probably boosts t/m and hybrid science at a cost to the pure attackers) but to me there are better ways to achieve that result if it is intended. I don't see that it achieves what you are hoping for - ie a mechanism for the BETTER kd to get something additional from war - because with a min gain of 1 you only need 1 land def prov and then everyone can hit that one (ie it is not the case that the KD who creates 5 land def provs will be able to make more abducts than one who creates 1, aside perhaps from the direct effect of it being 20 non land provs versus 24 which already exists).
I would be fine removing the -50% kills on abducts during war. Then it becomes (if it is not already) viable to hit in range to gain science, without the need for this artificial min gain mechanic.