Re: spare anchor
My primary on an 11,000# displacement boat is a 33# Rocna on all chain rode on the roller. Hanging from he bow pulpit is a 12# Fortress on mostly braided line, ready to quick deploy or be used as a lunch hook.
The Fortess is held in place in a vertical bracket mostly by gravity. A small line keeps its from bouncing out. Can be in the water in about 5 seconds. The rode can be rund to a stern cleat if needed.
I'd go light weight for a secondary.