While this suggestion I'm going to make doesn't do anything to fix safepali's and people not buying Rage to utilize them, I think it's a decent compromise.
Make it so for the purpose of player vs player combat, people without rage have 75% combat weight/effectiveness vs the 125% combat weight/effectiveness of the person with rage, putting the non-rage character at a significant disadvantage. If two people have rage they go back to having the regular 100% combat weight/effectiveness vs each other.
That way there is a tradeoff. Currently there is no trade off outside of not being able to aggro, it's just mostly benefits for skipping rage and that doesn't seem right.
If a change like this was made, I don't think we'd need to touch the safe palis. Yea people will be more safer than previously by abusing them when they couldn't in other recent worlds but that seems to be the intended effect the devs wanted anyway, the problem is that as of now rage just doesn't seem appealing at all for most characters so as bias as it seems I like my suggestion to remedy that.