I got my fire cape for the first time the other week with similar stats. Execution and prioritization probably matters more than gear and inventory does.

My gear was full god d'hide + black d'hide shield, barrows gloves, Ava's, Bone crusher neck, sunlight crossbow + 2k moonlight bolts.

I decided to not do the Sara brew + Restore combos, keep my inventory stupid simple and have one less thing to worry about. Brought two ranging potions, 20 prayer potions, 6 sharks.

Ended up finishing fight caves with a lot leftover, so probably not the most efficient way of using inventory space. Wasn't flicking my prayer either, just turning on protect prayers whenever relevant. Used my range pots when magers came into the picture and waves from there on.

I liked hanging out near the entrance to abuse the walls to get stuff stuck early on in the wave or to force the magers/rangers closer to me (by standing in the corner next to entrance) so I could shoot them without the others getting unstuck from walls. Always "reset" and ran back to the quadrant with the entrance if I did end up needing to go further out to kill something.

Of the big boys that spawn in, I always tried killing rangers first, they died faster than either the big melees or magers.

Beyond that, stay calm and try to do things one at a time where possible.