I will be leveling up most likely with a caster friend, are one of the buffers better for casters.
Any other advice would greatly appreciated. Thanks all !!
First issue to keep in mind. If your friend is playing a 'caster' (Spellhowler, Sorcerer, Spellsinger or Necromancer in full caster mode.) then playing a buffer helps *them* but doesn't give you much to do besides picking up drops and rooting an occasional mob. (Assuming you are both leveling with BSPS, and doing without is quite frankly not much fun with a nuker.)
Buffer + archer is much the same. They kill, you just pickup and occasionally root. This is why 90% of the 'solo' archer and nukers all have a boxed buffing char on a second account permanently attached to their posterior instead of partying with a 'live' buffer.
Buffer + melee is far more 'playable'. By that, I mean both players are useful and have something to do as well as fitting in fairly easily if you find or start a party.
If your friend is going to stay a caster, then the best thing you can do if your going to level together is to play a complementing caster as well. Or an archer, that way you are both ranged characters and neither of you is left 'holding the bag' so to speak. I would however suggest that you might wish to play 'complementing' characters if you will. That is to say, each of you play a different class and play your strengths off each other. A fair amount depends on what class your friend is going for. As some go together better and some just depends on how well you play together.
Regarding buffers though. There are really a limited amount of really needed buffs. Ignoring buffs like Might or Shield, which are pretty much given to all buffers, broken down by combat type they are:
[Melee]
Vampiric Rage
Haste
Focus
Death Whisper
Agility (Only if an evasion based class though.)
[Archer]
Wind Walk
Focus
Death Whisper
Agility
Berserk
[Nukers]
Acumen
Empower
Bless the Soul
Berserk (Not really necessary, but it is one of the few buffs that not only help nukers. But also has far more benefits for a nuker and less drawbacks than it does for melee.)
[ALL]
Bless the Body
Bless the Soul
(Added here because while not necessary for any of the classes, these are still equally useful for all classes nonetheless.)
This roughly splits the 'functionality' of each buffer based on which part of the buffs they get.
[Elven Elders]
These are really more healers (like the Bishops) than the rest of the 'buffers'. The vast majority of their buffs are 'defensive' in nature and they are not one of the popular buffing classes. They can work fine with another melee, having plenty to do just by healing and giving their defense/resistence buffs, but with a nuker or archer they are going to be stuck just giving recharges or rooting things at best.
[Shillien Elders]
Ah, the Dark elves. One of the more popular buffers. SE's are pretty much one half the 'good buffs' for both melee and casters. They get Empower and recharges for the casters and Vampiric rage, focus and death whisper for the melee. Heals were nerfed slightly in C5, but they are still a decent character overall.
[Prophets]
The 'Other half' of the good buffs for both the Melee and casters. They get Acumen and Berserk for the casters, and Haste, focus and death whisper for the melee. They also get the very useful Bless the Body and Bless the Soul buffs that help both classes. (For now I am ignoring their late game 'Prophecy buff', although it is another skill that is fairly decent.)
Comparing the Prophet and the Shillien Elder, the Prophet gets more buffs, but the SE continues to get heals. (The prophet stops getting them at L40.)....and now on to the Orcs.
[Warcryer]
This is the best Melee buffer, simply due to the fact that they get all the best melee (and most the archer buffs.) The names are different but the effects are the same. They get Haste, Focus, Death Whisper, Vampiric Rage, Agility and they even get Acumen. (Their only 'nuker' buff.) They also get a physical version of the "Blazing skin" buff that reflects damage taken back upon the (melee) attacker. For now I will ignore 'Chant of Victory' as this is a late game buff (It only lasts 2 minutes not 20) and given the cost (Both in MP and in adena, since it uses spirit ores.) you probably won't be using it all the time. Oh, and Warcryer don't get Wind Walk. (A minor omission, but still noticeable.)
There are some downsides to having all these buffs however. First downside is that you get them much later in the game at higher levels than the other buffers. And the other main issue, is that these are all 'party buffs' and their MP cost reflects this issue. Thus if you cast all your buffs, it's going to take a significant amount of your MP to do so, although this has the side benefit of allowing you to buff a whole party much faster than the other buffers.
Warcryers also have one 'Heal'. Chant of Life, this is a 'pure' 'heal over time' and does not benfit from shots. (other than cast speed...and it needs it!)
[Overlords]
Finally....the red-headed stepchild of Lineage 2. As far as a buffer goes, the OL is more suited for nukers than melee by a long shot. They get Acumen, Berserk, Wind Walk and Empower. For melee all they have is Agility, Bless Shield and Death whisper. Well, sort of. They max out the few buffs they have slightly sooner than a warcryer, although they start getting them later. But they don't get Death Whisper or Empower until they are L77!!!!! At which time they get their first (and ONLY) levels of those skills, although they are at maximum power.
Overlords get one heal as well. Heart of Paagrio, is their heal and it is half instant, half 'over time'. Thus they do benefit from shot use, and it is a fast casting heal.
Not only do Overlords have many of the same issues as Warcryers do with the lateness of their buffs and high MP use. But they have the added distinction of being a buffer poorly suited to be 'boxed, unlike the Prophet or Shillien Elder as they are almost completely replacable by potions until they are nearly at the Level cap.
The issue here, is that either a Shillien Elder or a Prophet can make a good buffer for a nuker, when supplemented by potions you can buy at almost any time, but the only thing an Overlord has that cannot be carried in a potion before L77 is Berserk. And that is the one buff that does the least for a nuker out of all their effective buffs. (And if you want it that much, a Prophet has it and other useful buffs as well.) In constrast, a Wacryer does quite well fighting alongside the characters he has buffed.
For most 'casters' having a Shillien Elder or a Prophet along to buff, simply breaks down to one thing. Do you need Empower or Not? And for the most part, a casters damage is high enough that it isn't always necessary, despite being the best way to add a noticable boost your a nukers damage. Spellhowlers and Necromancers might prefer Prophet for the "Bless" buffs + Acumen/Berserk, while Spellsingers and Sorcerers might prefer a Shillien elder for Empower + Recharges. Although some have been known to box *both*.
NOTE: The following buffs can be bought regularily from either the Trader of Mammon, other players or even the General stores. (If you don't mind them being lower level.)
Haste
Acumen
Wind Walk
When comparing the above buffers, it's helpful to keep this in mind, as you can 'supplement' (or replace) missing buffs with potions and all it costs is a bit more adena...I won't go into all the ways an Overlord is and has been gimped for now...but if your still stubborn enough not to give up on them yet, just let me know and I'll give you the rest of the dirt on them. (It ain't pretty though.)