A farmer Jane will be more versatile. If conditions are good maybe you just paddle with the Jane and if its worse you can add a neoprene jacket… or don’t even bother with a jacket. If your paddling is limited to good weather you could get by with just the Jane and whatever upper body wear you think you need. I know I would think the sleeves of a wet suit jacket would be a little restrictive to wear all day. But it would be extra warmth for rescue practice or rolling practice when you will definitely get wet.
As for a dry suit they are the ultimate protection and expensive. A dry suit provides protection to keep you dry and that’s all. You add whatever insulation layers you need underneath from a tee shirt in good weather to fleece upper and lower in March in Ucluelet. It also takes a while to achieve a lever of comfort with the gaskets to loosen a little and you to accept the restriction.
If you start with a Jane they are always useful because there are conditions where it is everything you need, summer paddling for instance. If you expand your seasons or paddling destinations add a dry suit then.