Help! Choises and an Small thing

[HunterICX]

Well...I need some help here...

I,m running Grey Wolves.

Now, I,m still in the Type IIA (1940 7th patrol). and I,m thinking about buying an new submarine.
So I just went looking into an sort of Map with all the subs and upgrades on it (in game career by U-Boat and then the ? Button)

Now...I like the type IX...but when I see the VIIC/2 Conning tower in 1944 You can place 3 Flak stations on it Holy Hell... now I cant Make up my mind I love the IX of its size and the amound of Torps it can carry . but that Conning tower took away my breath.
also wich Flotilla is the best to be at? (currently in 1st Flotilla)

So what would you guys advice?

*small thing*

I see people with grey wolves and their sub has an different skin on it...How do you activate those for your sub?