Gravity Bow for yourself or Lead Blades for friends; Upping the effective size of your weapons is always nice for a level 1 spell, and it becomes even more dramatic if you have enlarge person or oversized weapons in the party
Protection from Energy, Communal; it can soak up some splash damage if that's a common issue you expect to fight
Ice Slick, to grease an area and knock up to four medium sized enemies prone might be okay if you don't mind them taking the +4 AC bonus to you specifically, but it will help your friends out and depending on the terrain could last indefinitely
Sound Burst for potential to stun a 2x2 area is also to be considered, if you're looking at more area-of-effect debuffs and Ice Slick doesn't work for you
Ironskin, because natural armor is powerful and you might get caught alone or just by a stray bolt
Carry Companion, if you expect casualties, travel issues, etc.
Summon Nature's Ally 1-4 for some reinforcements and to keep people off of you and your friends; some of the creatures summoned have some potentially useful abilities, like Constrictor or Venomous snakes and Crocodiles.
Named Bullet, to give your bow (And other's projectiles) the ability to strike against touch AC
and finally, Bow Spirit, so you can free yourself up to do other things and still get some damage in, or just get a bonus attack at your full BAB.