Welcome Sarah
Can I point you to the Share your travel tips section on these boards as the AGE question is on there. You would be in the younger age bracket
I have done 8 tours there is a video on here from me Cindy Nixon which might answer some of your other questions.
I have been on the Kenyan Safari tour which was amazing. SO if there are any questiones re that tour ask away and I will try and answer.
JY cannot confirm that you will sit with another fellow traveller they try and block book seats, so it is odds on you will ne at least near someone if not next to. I don't need to sit with someone on the tour group as I really don't like flying that much so I need peace and quiet!!! ha ha ha.
I can understand how you feel but this is a very safe way to travel to see the world and meet a great bunch of people along the way, I did the add on on this tour which was well worth it to laze around, it was fantastic to see the animals running free.Lovely memories.
Cindy