I dont think we need more then a few solid players both for first 11 but also for cover and different positions.
I'll think all of the players mentioned are not unrealistic in price and availability.
First of i think our main objective should be to sign a quality CB.
1. Vertonghen. Experienced, leadership qualities, can play on LB aswell, could form a good partnership with vinnie for Man City aswell for Belgium.
2. Mangala. His price tag in very steep, but we would get a rough diamond. He is fast, good anticipation, is a bit rash but that can be trained out.
3.Kyriakos Papadopoulos. I rate him highly and he could be the stability we need for now, he would fit the bill for me. (For now)
Next, i think this is controversial, especially as we are severely lacking englishmen but i just don't think Joe Hart is good enough for where we want to be. Not having stability in the back has really cost us so many points and headaches, and at top level small cracks will always show and cost you dearly.
1. Casillas. Nothing needed to add.
2. Courtois. Getting him would probably be better for us then Casillas, as he is younger, but i don't think we would be able to get him unless he had a secret buy-out clause.
3. Valdes. Quality keeper
Bonuses.
With reports about us already getting Bruno zuculini, Fernando from porto could really be a big plus for us. It would remove a lot of concern about either Fernandinho or yaya getting injured.
I rate Isco as highly as Hazard, both worldclass players in the making. Pellegrini already know how to get the best out of him.