Hey Dafu,
A lot of people like to have a dedicated 4-way for games like Pac Man, Ms Pac Man, Donkey Kong, Elevator Action, etc. Using an 8 way for those might sound good in theory, but really is erratic in controls. What many do, and what I'd recommend is to get a joystick that is switchable from 4way to 8way. Mag Stik Plus is a nice one that allows switching from the top (joystick itself) rather than needing to open the control panel.
As far as the spinner goes, you'd miss out on some popular games such as Tempest, Arkanoid (all 'break out' type games) and Tron.
A popular spinner is the Turbo Twist 2. My understanding is that it can be mounted in the same size hole as a pushbutton so really, it doesn't take up too much real estate on your CP.
HanoiBoi