What about Aluminum hulls?

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Pro, light and strong.
Con, floating Alka Seltzer.

Make sure you, or any electrician do not allow any copper tailings to fall when snipping wires. They make cutters with rubber in between the blades to hold the tailing, then put them directly into a plastic bin for proper disposal. Make sure you use them and any electrical tradesman coming onboard uses them.

When passengers come onboard, hand them a Tupperware bin to put their change in. It's amazing how fast a penny (or any copper containing coin) will eat a hole through the hull if there's any salt water in there.

You will always have problems with paint and fairing compound blistering, prepare yourself for it, it's inevitable. Get good at spot repairing because you'll be doing it with some frequency if you don't want your boat to look like it has leprosy. Aluminium hulls are good for about 30 years before you get into crystallization issues. You have to make sure that you use bottom paints for aluminium, most contain copper and will kill your boat.

Aluminium is easy to work, form, weld and repair. Material is relatively cheap and omnipresent world wide. You can mix and match most alloys which allows you to plate with corrosion resistant 50xx marine alloys which you can't "T" and use 6061 T-6 extrusions for light, stiff stringers on the inside.

It's a bit on the noisy side, but all in all, there's nothing particularly wrong with aluminium as a boat building material.

The sky is not falling on aluminum boats and you don't have to beg your guests for spare change.

Henning's memories of aluminum boats sound like they originated in the Bayous when the Thibadeaux clan built them out of war surplus aircraft sheeting.

There are enough examples around that you can walk the docks and see for yourself and talk to the people who actually live with them. Don't succumb to fear mongering.