As much as I love Paros I completely disagree with this statement. Santorini has a geological history that none of the other islands have. If you are interested in that kind of things you can not say Paros and Santorini are the same.
The high speed ferries tend to be less reliable when it's windy ( they will have more delays) but the boats are all more or less the same. Which ferry you take depends on where and when you want to go.
This year we went with Bluestar from Santorini to Paros (no delay), from Paros to Ios with...
I don't know which transit you mean.
Check-in is regular if you have filled in all the right documents and had your tests or vaccinations. When you haven't you will be requested to do so first and come back later.
Customs was also regular. No waiting time when we went ( in the evening)
Andros, Tinos and Kefalonia tend to be the most windy islands.
On every island you will always have some wind. Sometimes it's more and sometimes less windy.
Yesterday (Friday) on Ios there was really no wind at all. On Monday it was very windy. So it changes.
Price of sunbeds varies. Some it is just have a drink of the beach bar and beds are for free. We paid 3 euro per bed, 7 for a set or 10 for a set. Most expensive ones we have seen were on Ios, 50 euro for a hanging sunbed in a cool club.