There are a number of reasons I HATE Tavnazia.
1. Only 18 people - It is not that this zone is hard to fill up, it's that it screws over A LOT of people who may wish to attend. It is too much work to organize 2 runs at once, so essentially 15-20 people miss out on getting to go. In comparison the other CoP zones usually only screw 3-6 people out of coming.
2. $$$ - It is an incredibly expensive zone to do, for some people that really sucks
3. Farming Trouble - Doing the pulls in such a way as to make farming reasonable is next to impossible, you are going to end up having to do shitty sets of fight, where each set is going to be a mix of mobs that drop hydra gear, af2, af2+1, etc. I dislike this because I would like to be able to aim for certain farming goals, i.e. we can do Xarc for Xarc AF2, not be forced to fight all the different types.
4. Clear is worthless - There is no reason but storyline to clear, while that's all well & good if you want it, that makes it hard to reason to keep going because once some people have the clear there is almost no motivation to clear for others, and there are always going to be people who *WANT* the clear on any given run and you have to draw a line somewhere as to when not to do them. In addition the clear is a real real pain in the ass.
It's just a real headache to do and doesn't work out as very worthwhile in my opinion, I think people are much better rewarded for their time with DX in every other zone.