Hi Drifter!
It is so sad that Vi isn't on here anymore
She helped me greatly with my one trip to Portland in 2017. We were there for 8 nights and LOVED it!
I don't have too much advice, other than very highly recommending Reach Falls! It is absolutely beautiful, especially if you go up the falls with a guide. The beginning may be a bit intimidating (climbing up the falls), but as long as you have water shoes on and are a mobile person, you will do just fine and I can guarantee that you will not forget it! I very much recommend flexible water shoes, not Keens or Chacos. LMK if you have any questions about visiting Reach Falls.
I also highly recommend going to the craft market in Port Antonio. If you've read Vi's trip reports, she mentions Rock Bottom, the wood carver. He is a great guy and does beautiful work! There are a few little shops/stalls with cute, inexpensive souvenirs. And when we were there we enjoyed smoothies and breakfast at the little restaurant in the market (on the left while facing the water). I believe there was a bar there too.
You didn't mention Frenchman's Cove, but I would also highly recommend a visit there if you feel like relaxing on the beach, taking a dip in water, swinging over the water and maybe snorkeling up the stream. I honestly thought that Blue Lagoon was a little overrated and would choose Frenchman's over it. But it was also overcast and very windy when we were at Blue Lagoon, so that could be why.
Enjoy your trip! I am definitely not an expert on the area, but I can tell you that we will be back
BTW - I don't think we ever had to get cash during our visit, so IDK where an ATM is. We must have brought plenty of J$ from Negril to cover our visit to PA.