I stayed at the Tassia Studios 4 years ago, so I can only comment on what it was like then.
To be fair, firstly, I'd say that the hotel is ideal for young families and couples, and NOT large groups of singles. For said large groups I would advise that you stay more in the centre of Laganas, at hotels with fellow guests of a similar age group where your needs are more readily catered for.
I would agree that Kostas is quite strict, however, he needs to be in a lot of respects as there was quite a bit of rowdiness in the early hours during my stay (it's not fair on older people or children to be kept awake by drunks, of any age, during the night, of which there were quite a few.) I would imagine if there were too many complaints then his hotel could come under review by the tour companies. Kostas is an extremely hard worker, as are the various members of his family, and I was very impressed by this.
The hotel is a 30 minute walk from Laganas town centre and the beach, so please bear this in mind. The food was home cooked, nice but simple. Entertainment was typically Greek, with theme nights, otherwise it was a bar, cafeteria and big screen TV/films every evening.
One last thing, to get into Kostas' good books, tell him you have been a life-long Olympiakos fan (that should do the trick!
) The reason why I haven't been back since then is that I now tend to go to the larger hotels in the Greek islands that do all-inclusive
or half board
I wish Kostas and his family well.