Features - Should I go for big or numerous?
It's all up to you. There are pros and cons to both and it depends on your use case.

Generally one would tend toward decoupled functionality with granular features instead of a giant feature. Especially if you wanted to potentially use these features on other sites.

Some information to help you out.

One big feature Pros:


It's quick and easy. If you're just using features to track database changes in code and
don't care about re usability, you can just stick everything in one
big feature.


One big feature Cons:


If you make one big feature, you can't re use it at all on another
site unless that site is almost exactly the same.


Decoupled features Pros:


You can re use features on other sites.
Your features are much more manageable, even it if it takes a bit
longer.
You can keep custom code which is directly related to the feature in
the features module, so you're keeping the feature + custom code in
one nice package.
This model fits in well with programming in general, taking big
problems, breaking them down, abstracting them, using dependencies,
etc. It will definitely improve your programming practising
separating your code logically like this.
Helps the way you think about Drupal components and how they mess
together.


Decoupled features Cons:


Overhead of organizing features structure. This will get easier as
time goes on and you get better.
Can be very hard to decide where to decouple, especially for newbies.