We have always opted for first sitting at 6:30 p.m. and never felt rushed. However never booked any full day excursions just the half day in the mornings, so had the afternoon to relax or DIY explore in the port.
After dinner we go straight to the theatre to see the 8:30-8:45p.m showing. This finishes about 60-90 mins later, still giving time to wander the ship and have a drink somewhere before the kids are exhausted and ready for bed. If we went for the late sitting felt we would miss out on some entertainment. Its personal choice at the end of the day.
Food for thought!!! if you go to the second sitting for dinner [8.30-8.45] you will in all probability not leave the restaurant until 10.15 pm. It does not leave much of an evening does it? We always do first sitting now,as you leave the restaurant at about 8pm. This gives you a full evening to do your thing.By all means go for a large table, you nearly always meet other people of which you will get along with.
Always booked second seating for dinner. If you are doing trips as we do, you dont have time to get ready early enough. We took our two grandaughters 11 and 12 last cruise in april this year and no way had we time to get ready for first sitting. Husband said he needed something like a car wash, spinning brushes and clothes ready at other end. Girls with hair straighteners, curling tongs, make up! Take up too much time. We always had time to go to shows, the girls had more energy than us! We are still catching up on sleep! Enjoy yourselves! We did.
There are for and against regarding which sitting, if you are on 1st sitting and have been ashore and want to be on deck for sail away then 1st is a bit rushed and as with 2nd a lot of your evening has gone if you are not out of the dining room before about 10.30.
Why not try freedom dining on Ventura I'm not too sure of the times but I think it is something like between 6.30 & 9.30 you just go along at whatever time you like and will be seated at a table size of your choice and of course you will be meeting new people all the time. I didn't really like this idea so we opted for the main dining room but we spoke to lots of people who had chosen this dining and they were very happy with it, in fact there were several people who liked their table companions so much they chose to eat with them every evening.