I played on another RSPS about a year ago and they've since closed but they had a boss (it was a custom boss) that could drop the Telos weapons from RS3 (Seren Godbow, Zaros Godsword, Staff of Sliske) and they were BiS. Now im not saying they need to be BiS, but I think they'd:
1.) Look super cool because lets be honest, they are good looking weapons.
2.) Add and intermediary step between mbp > tbow / vork whip > sov
3.) Another boss for players to fight, because who doesnt love variety?
Just a thought