Para arcos, você precisa dizer o tipo de arco. Por exemplo arco longo ou arco curto.
Arcos compostos usam os mesmos talentos que a variante não composta da arma.
da descrição do arco longo composto:
For purposes of Weapon Proficiency and similar feats, a composite longbow is treated as if it were a longbow.
Para raios, foco de arma (raio) & especialização em armas (raio) é suficiente.
do faq (grifo meu):
Weapon Specialization: Can you take Weapon Specialization (ray) or Improved Critical (ray) as feats? How about Weapon Specialization (bomb) or Improved Critical (bomb)?
All four of those are valid choices.
Note that Weapon Specialization (ray) only adds to hit point damage caused by a ray attack that would normally deal hit point damage; it doesn't increase ability score damage or drain (such as the Dexterity drain from polar ray), penalties to ability scores (such as from ray of enfeeblement) or drain, negative levels (such as from enervation), or other damage or penalties from rays.