Tbh i wasnt going to put guardian in there but thought why not and see what people say, but zenyte on the other hand are something that shouldnt be hard to get at all. we have a fury worth 10M then we have the saradomin amulets worth 50M then BOOM zenytes 5B+ because of how rare they are. currently the drop rate is 1/566 however on OSRS they are 1/300 and still sometimes very hard to get depending on RNG. So i still think they need to be dropped massively.
Nex has always been a boss no one really wants to kill. due to its crappy basic drops and the mechanics it involves. I've always said removing the phases and just having nex to kill would bring more action towards the boss, but thats just my opinion