First of all: do you need OS/monitor/keybord/mouse?
1)You said gaming right? Titan black and 780(ti) may both use gk110 but 780(ti) is more gaming oriented . So your best single gpu gaming choice is 780 ti and not titan black.(why spend that 500$ extra?).
http://www.pcgamer.com/2014/05/08/gtx-titan-black-the-ultimate-gaming-gpu
2)You said you prefer 350D but that's a micro atx case. You can get another obsidian atx case which pretty much looks the same, and you will be far more comfortable fitting the parts in the case+ extra air flow for better cooling. If case size is a big deal for you can stick with your choice.
PS. Spending that kind of money and playing on a simple singe Fhd screen is just wasting your money...