Even if you have 50 composite bow skill already, +11 does help. Like 2handed weapons, bow also gets two-handed bonus in dps formula afaik. So bow dmg still slightly increases over 52 composite skill.
In fact, hunter is one of the easiest class to template, so there is no reason not to include +11 bow even for melee hunter.
If you rely upon a base weapon spec line for styles or 2H damage, then every point is worthwhile.
Bows don't have style damage, but do get 2H damage bonus. Crit shot is simply 2x damage. Increased Crit Shot levels simply reduces draw time.
TWOHANDBONUS = 1.10 + 0.005 * SPEC
In other words, you get a default 10% damage bonus for a 2H weapon, with an additional 1% damage bonus for every 2 spec points. That +11 Bow gets you 5.5% more damage. One major issue with Archery damage comes from lack of buffs (STATS) which reduces your damage modifier.
Composite 52 spec maximizes your possible damage modifier for that particular weapon type, but it also takes into consideration your stats, relics, and enemy level/armor/resistance. The formula below is what Phoenix uses with the bold aspect the relevant section. NOTE: a value of 25 is substituted for RANDOM(50) providing a static averaged variance. SPEC = 52 maximizes your damage to match the MIN function requirement. Against a level 50 opponent, anything over 52 is irrelevant for Damage Modifier calculation; anything less will result in less damage.