The biggest issue is the people killing for these drops are not the ones that need them , basically it's just a mid level selling instead of a high level selling lol. Target lock for all it's good intentions is a failure IMO . It certainly does not limit griefing it just changed it that's all.
ABOLISH TARGET LOCK
I agree with this target lock will just slow high lvls down. But with the immense wealth some people have they will either have alts or buy/lvl accounts to an optimal level and then proceed to pimp them with impossible gear. Take a lvl60 with full met gear grandfathered in for example and all the best lux/items. Ppl will have zero chance again.
A few of these dedicated campers and we can kiss goodbye to the mid levels harvesting anything profitable from bosses on a regular basis. Give it a few weeks to months it will be back to nearly as bad as before.
Also you can be ksd with the current system on mob of same lvl quite easily. Players with full lux gear can one hit lock and run around insta locking all mob in the area. Don't have awesome weapons, offhand and damage gear? Sorry u have no chance when someone wants to mess with you. The 15% or so makes it easier to ks in this case, not harder.
Overall not a bad idea but so far I haven't seen much improvement as a whole.