I fully anticipate to get flamed for this radical new concept, but have you considered that the higher tier players ganking of confused new players is maybe the reason the game dwindles down to almost no one after the shine of the new world wears off? It's a barren wasteland out there.
It's simple: new players do not appreciate constant frustration without a sense it's worth something. There's a difference between losing in dark souls knowing you can try again, and losing EVERYTHING in haven and hearth. People eventually get sick of just not having fun (remember when you played to have fun? weird, I know) and move on. I understand PVP is a big part of the game, so here's my proposal:
A two week grace period, 14 in-game days where other players can't touch noobs. This means they have both more time to get to grips with the basic concepts, and motivation to get better at the game knowing the sword of damocles looms overhead. After all, the moment that timer ticks out, their arse is grass. I feel this might extend the life of the game if new players feel more invested in the game rather than "this sucks, i'm moving onto something else."
Right now it seems like everyone is holed up in their big fancy realms not doing anything much. I've never seen another player so far (but received dire warnings over realm chat that I'm very lucky). I'd like to see H&H sustain itself over a longer period of time, and as much as you may cringe, new players are content too. No new content, no new player interactions, no reason to play.