YOUI insurance cover boats under 12mtrs. well worth a quote. i saved about 30% of my nautilus policy

Nautilus Marine have been good so far - although I have never made a claim.
Trident Insurance are absolutely terrible - very shonky - and I never made a claim with them either.

I have YOUI with the claim climb up to 80% of the boat value, no problem there.

I use RACV in vic, so for WA the equivalent should be ok?

I am also insured with Pantaenius ( www.pantaenius.com/au-en/) easy and helpful and stress free, They were more than happy with racing insurance and with none of sill restrictions that some have for distance from land or distance sailed.

Altho still have the "off the beach" cat insured with QBE

The principal consideration with any insurance is what happens when you claim. Coverage, conditions, premium etc are important but the reason you get insurance is to transfer your risk to the insurer. If they don't pay up, and a helluva lot won't in lots of circumstances, the insurance is pointless.
The best way to reduce this risk is insure with the companies with a reputation to lose.
The trouble for many of us is these businesses often don't insure yachts on moorings.
I questioned all the major insurers about a hypothetical claim for my mast going over the side in bad weather. All three said if I hadn't hit anything they would put it down to wear and tear and not pay. If it ever happens to me I'll swear I hit a whale, submerged container or Noah's ark.