That's a pretty vague question. I'll answer the best I can with out being to vague myself.
As far as Best CASE Scenario you'r going to want one that will house what ever hardware you plan to put in it for the next 5-7 years. You are always better off deciding what hardware you want before deciding on a case. The main reason for this is you do not want the case to limit you. A case is just a box that houses your hardware. When I'm creating a build log I generally plan it in this order.
1. CPU - What platform (AMD/Intel) and Generation (Kabini/Skylake) e.g. socket
2. Motherboard - What form factor, features needed (ATX/Raid/OC ability)
3. GPU - (AMD/nVidia) what res will we need etc.,
4. SLI - Generally No
5. # Drives SSD's and old school spinners
6. Cooling - Air, AIO or Custom Water
7. Accesories such as DVD-roms, Bay Resevoirs, pumps, Rads etc.
8. NOW we can start looking at cases to determine what will work for this build. (Full tower, Mid tower, mITX)
So, there are just way to many variables to go into what the best scenario is. I will say to buy a good Brand name. They tend to have better options and better customer support if things go wrong. Also consider warranty. Generally cases don't go bad as there are few moving parts, but it does sometimes happen.