It isn't just standard action attacks, it is any event with a single attack. Attacking on a move action, attacks of opportunity, attacks with weapons like firearms and crossbows that demand a reload, that stuff. The goal, of course, is to make single attacks and intelligence of value to weapon-using classes and make specialists suck less ass.
For example, you have a 5th level rogue with a rifle. The weapon demands a two round reload after every shot, but it deals a beastly 2d10 damage with a 120ft range increment. Having aimed attack and improved aimed attack makes it an extremely nasty weapon with EXTREMELY long range, and the "sniper" (sneak attack works within one range increment) and "far shot" feats compliment this for a 180ft sneak attack for 2d10+3d6+FTGiP*, and rogues need Int already.
*"**** this guy in particular".
Now let's put you in melee with a fighter. You have to close distance and attack with your sabre, so normally you'd deal 1d6+4, or ~7.5. Now, your closing attack deals 1d6+6, or ~9.5. Your attacks of opportunity becone increasingly weak with levels as well. Not so with aimed attack.
Combine with Against the World for maximum effect.
I also need it to not be worthless.2. Adorable is an interesting idea, but I can't see it working on animals and other low-intelligence creatures. Many predators prioritise young animals over adult ones. They don't see them as cute, just as an easy meal. The concept of finding other species cute is largely limited to humans.
Because once death becomes understood as an inevitability, it's hard to fight it with that kind of fervor. The people who are taking that feat don't understand yet that they HAVE to die, it cannot be avoided forever.3. Go Down Swinging is awesome, but I don't understand why it's age-restricted. Sure, it's hard to imagine an old man making a flurry of attacks like that, but the same goes for many feats. Is combat reflexes, for example, also age-restricted?