Go with what you can demo paddle. The plastic tempest 170 is a great choice. The poly Valley boats like the Aquanaut or the Etain is another good choice . I just demo'd a bunch of boats and the Etain was my favorite. The dagger alchemy is a much smaller and slower boat, great for rock gardening and surf but slow for a touring boat. At 230 lbs you are probably over the design weight for the low volume version. I don't think you would want one as your primary boat but it would make a good rock basher later on.
Assuming you are in the SF bay area, I would join BASK and start paddling with them. The sf bay is a fantastic but complex place, lots of currents, wind and rock.