Hey! I had the same dilemma a few weeks ago. I think your ceremony is right, I wouldn't change it to 5 because you'll run out of time pretty quickly. Our photographer said 1.5 hours before sunset is the best time for pictures, so if your sunset is at 6, the best time for pictures is 4:30.
The ceremony usually takes about 15 minutes to half an hour. We're going with the shorter timeframe because we're not doing a sand ceremony or anything like that, so we don't want it to drag out for too long with speeches and things. So, let's say it takes 20 min for the ceremony, that takes you to 4:20, then you can take pictures with a few family members and guests until 4:30 and then go to take your couples pictures. You can always keep taking group photos when you come back, before dinner is served , if you missed anybody because you didn't have time. A bride on here suggested that you have a list of guests that you must take a picture with, and have someone move things along by going through the list.
For the reception, I'd do 1.5 hours to 2 of pictures and then have the reception. That would take you to 6-6:30. If you decide to go with 6:30, that would give you enough time to take sunset pictures and everything . As for your guests, we're leaving it up to them. We will probably have an MC suggest a bar they can head to in between, but some people might want to go to their rooms and freshen up. Some like to change to something a little more evening appropriate. I'm sure they can find something to do . The sun will be setting so even sitting by the beach as the sun comes down with a drink in hand sounds like a pretty sweet idea haha (that's probably what I'd do )
Here's the link to the tips that our photographer has for the timeline suggestions. He has it divided by months too: