Should I get better magic/pyromancy, or just get lightning bow?

Which is better for ranged attacks?

For powerful ranged attacks, you're going to want Sorceries. The Soul Spear and Soulmass spells can deal a huge amount of damage with a good Int. If you're Int isn't very high, just stick with Pyromancy. Pyromancy is slower and has a smaller range, but it's still does a fairly decent amount of damage.

Bows kinda suck in Dark Souls, don't use one. If you absolutely must use a bow, try out the Dragonslayer Greatbow.

i'd have to disagree partially
yes, the dragonslayer bow does good damage, but the arrows are absurdly expensive, only uses one type, and the bow itself is rather heavy
any other bow though, the elemental upgrades aren't exactly the best option, since it removes all scaling
if you are using either an int or faith build, it's viable to upgrade through the respective paths (int=magic/enchanted fai=divine/occult) and use the moonlight arrows (but you run into the same issue with cost per arrow). Doing that, however, does allow you to use other arrows; such as poison, if you want to weedle something down from afar
if you are running mostly str, your only real options are compound bow (lowish range, quick reload, pretty decent damage) with the normal upgrade path or the before mentioned dragonslayer bow
if you are running dex, you can use any of the other bows with the normal upgrade path, although pharis's bow has the longest range

ultimately its up to how your character's stats are set up and what you wish to do

Buying magic spells seems cheaper in the long run than buying expensive bows and arrows.

INT build = sorcery and pyromancy

DEX build = bows and crossbows.

If you have a DEX build, don't be afraid of upgrading a good bow, bows are excellent at PVE and crossbows can hurt in PVP. Once you have a good spot to farm souls, you won't be having problem with ammunition

LOL carphil why does Pyro have to be in INT build?

Look if you want some magic, get pyromancy, only thing you need to do to make it better is upgrade the pyro flame, easy to do on any type of character then upgrade attunement a little so that you can have spells (how many is up to you)

I always if I'm making pure dex or str build i use pyro with it.

and in my humble opinion bows are almost worthless unless you bother to upgrade them.. Even then better you get physical weapon worth a damn than a bow.

Pyro does not have to be in a INT build, however, is useful for mages.

meh, you and your hybrid magic builds, makes me sick.

i think you should have to choose in my opinion, having the option of firestorm/tempest and great combustion but them HCSM and crystal soul spear doesnt seem right to me XD

Look, I lost countless souls and humanity at Duke's Archives with my mage because I had only sorcery and an enchanted estoc. The crystal enemies have 80% defense against magic I think because I had to use 3 souls spears at one crystal hollow or hit them 10 times with the rapier. You don't have ideia how crystal cave was dificult. So after this, I aways get at least fire orb to help me out

lol I would know your pain EXACTLY except mine was only a mere Magic+5 Iaito

going through dukes sucked quite a bit for me... but did it eventually, i found out lightning spear from my inventory to give me a hand

I made a +5 chaos long bow recently use fire arrows. It has over 400 AR. Hits some enemies for 300+

Hm I have to disagree with almost everyone here. Pyromancy is not good for ranged. The range is pretty much next to melee and unless you have 45 dex then the casting is too slow for them to stay at range. Sorcery is the best option for range but if you don't have Int its not a option. Miracles are just terrible for range. The lightning spears go far but they are god awful slow to cast and throw. Bows are good. I beat the entire game with a +5 Lightning Longbow, Dragonslayer Bow and +15 Pharis bow and Avelyn. No shield no melee weapon. The dragonslayer bow is only good if the enemy doesn't know you are there otherwise its too slow like the lightning spears. The Avelyn is the 'melee' bow when the person is getting too close. +15 Pharis is for when your dex is 40+ and the +5 lightning longbow is for every other instance. The only boss I struggled with was S&O because my Avelyn was lightning and that was my boss weapon.