Different weapons are more effective at inflicting banes than others, so that is a key thing to consider. In addition, you can get them to have properties from Extraordinary Crafting, some include Deadly, which gives additional advantage to attacks.
Feats are actually pretty big. They are what can change encounters, combat or non-compete.
There are quite a few feats, but feats are what make your character a character. The are also used to explain/establish races for some campaigns.
Honestly, compared to all the choices there are in classes in other games, there really aren’t that many feats. There are some that require pre-requisite, and if you use the heromuster opened character builder, you can view just the feats you are eligible for based on your Attributes, etc.
When making an encounter, the feats that the NPC have are what will really determine if the encounter is easy or challenging, so likewise, characters without feats will be hard.
Now, you could start them out without feats, allow them to play and figure out their character and then pick feats after that.