I think he could be a cap casualty, and I'm fine with that tbh. I like what Zadorov but I'm not interested in giving him 4.5M+ for 5+ years, I'd offer him a 4 year deal max.
Soucy and Hughes are back as LD next next season and Soucy costs less. Canucks already need more punch in their top six and will be looking to probably keep Joshua. I'm not sure there's enough cap to keep everyone, even with Myers and Cole maybe not coming back.
Pettersson's deal is kicking in, keep Joshua would necessitate a pretty solid raise. We probably need at least another top six player to with Pettersson, Miller, Boeser, and Hoglander. Suter shouldn't in the top six, Mikheyev's a middle six tweener at best. We probably don't keep Lindholm, I'd throw his money into the top six. Bluegar may be gone too, he'll need to be replaced with an NHL level body at least, I'd assume Suter slots into his spot if he walks.
Myers is fine as an RD stopgap, one could probably have him on a 1-2 year deal to bridge between now and Willander stepping in. A short-term RD is what the Canucks should be looking for imo, whether that's Myers or someone else.
If he's willing to take 4 years or less I'd be open to allocating some of the money to him, but Hronek's raise is also going to eat into what we actually have to give and he's likely a bigger priority for management than Zadorov.