I've been to this exact resort as well as the one in Andalusia and Halkidiki but out of season so thankfully not £8k (we've a 2 1/2 year old so making the most of it!). If you book direct you can get a repeaters discount of 10% year on year.
The resort is beautiful but there is limited entertainment (some of it was a bit 'Butlins') and you have to book restaurants, the Tesla, sea cruise and kids club in advance. Our daughter is too young for kids club and wouldn't leave her at this age anyway but have seen on the fbook group I joined before we went that in school holidays the kids club at Odisia is already fully booked - including for October half term 2024.
We weren't able to use the Tesla when we were there (fully booked) and you can only book 3 nights in the restaurants in advance unless you're Deluxe. As there are a lot of families people wish to eat around similar times and I really didn't like the whole having to book before we were even there and sticking to.a strict schedule!
Also it rained one day we were there and there was nothing to do. They ran out of umbreallas and we asked for a buggy to take us to the restaurant as the resort is huge, the rain was extremely heavy and we were at the opposite end to the booking and it took an hour and a half to turn up...
Also whilst I may sound like one of these people (I promise I'm not!) oh my gosh the moaning of some guests made me embarrassed to be British. Yes it's not cheap and the service is usually amazing but wow the whinging that I heard was unreal over the smallest things and I was disgusted at times the way some of the other very entitled guests spoke to staff.
Out of the three I've been to Andalusia is the best one I would say, especially if you take the Tesla to Marbella for the day, though it doesn't have a good beach.
If you've school age children I would look at somewhere like Cullinan, Regnum Carya in Belek, Turkey. I was a bit snobby about Turkey before we went to Cullinan - it was actually more expensive than Ikos but everything was a level up, especially the facilities for children / teens, shows, drinks and buffet food.