I completed this trip this year and it was fantastic! I don’t think you will be disappointed at picking it at all. You think 37 days is a long time but it will fly by too quickly and you will be wanting another week. It can feel long and tiring but it is so worth it. 15 odd countries in 37 days is a huge feat.
You’ll have the main Pioneer group and there will be other smaller tours joined on from start to finish, so plenty of people to meet and get to know.
I found most of the places were pleasant to stay at. We did have hot weather the entire time and some places didn’t have air con or it didn’t work so we did struggle a bit. Most of those places you were only there for a night so it didn’t matter too much. Some of the hostels were newly renovated and really funky with rooftop bars, games rooms, communal areas and pools. There are hotels in the middle sector which felt like you were staying in luxury. I didn’t like the accommodation in Mykonos too much as they were pre fab tents, there were parties you could hear all along the coast line and fireworks that went off at odd hours of the night but they say you stay up all night in Mykonos and sleep all day but just keep that in mind.
Our trip leader was always very helpful and proactive when it came to our free days and always put suggestions up on things to see and do. She always asked when we were interested in doing and would go above and beyond to get the info and maps to us so we knew what to do. My recommendation is to do a bit of online searching on trip adviser on the certain places you are travelling to and see what there is to offer. Some of the optionals happen on part of your free day so it’s usually finding something to fill in before of after. We’d usually go for lunch, maybe go shopping or have a lazy day especially if we weren’t feeling the greatest. Sometimes just getting lost and exploring the towns is a good way to fill in your free days but I found with the pace and optionals we didn’t really have a lot of time to fill in.
But no matter what, you’ll have a fantastic time and I don’t think you’ll regret booking this trip at all.
I’m happy to answer any questions you may have too!