You should be able to break 500 with the Relic weapon at ilv114.

I think your opening rotation, along with how you are treating ToD is your hindrance.

I'm iLv117 with the HA weapon and I'm breaking 500 on a dummy naked consistently, even on a bad parse. (Not trying to brag in the slightest).

I'll explain my opening rotation, and why I do it the way I do.

PB > Snap > Internal Release (This is Key) > Snap > Blood 4 Blood > Demo > Dragon Kick > Twin Snakes > ToD (This needs to go up asap) > Boot Shine > True Strike > Snap > Boot Shine > True Strike > (DK Buff will drop here) Demo (Demo will have Twin Snakes buff though) > Dragon Kick > Twin Snap.

The key to this is the Internal Release, the quicker you start using it the better. By using it there, you are allowing yourself to use Internal Release on every 3rd Demolish (One of your most powerful skills. I believe it also lines up with every other ToD but I'm not exactly sure yet, your other, most powerful skill).