Agree about Plchotova but I like Pastulova as well only problematic positions libero and setter, both are very mediocre
By the way, I really don't believe that any of Final-Four participant get a ticket for GP in September if Germany, Turkey, Italy and Russia would play with their normal roster Especially if FIVB will give only 5 spot for Europe again
Probably it will be 6 spots for Europe, maybe one of them could be a wild card for Poland as usual, so in the final tournament there would be 3 more tickets (if both EL finalists get one). The problem of Russia, Italy and Turkey will be that it will be very hard to find motivation to play another tournament after OG, also depending on the performance there. I remember in 2008 the GPQ also was after OG and Italy and Russia did not use their best players but already some young ones who now are important players like Bosetti and Kosheleva. Either way I'm pretty sure Germany will take one of the tickets, they really want to play GP as preparation for ECH 2013 at home, and they have the whole August to prepare for the tournament while the other teams play OG, and we saw in GP how well Germany plays with enough time to prepare...
Concerning the number of participants, I expect 6 with round robin format...the question is just how they will choose those 6, by world ranking or by ranking of last ECH or whatever...RUS, ITA, TUR and GER can be sure to have a spot, SRB too if they don't qualify via EL, POL too if they don't qualify via wild card...apart from that I think NED and BUL could probably play there.