http://www.enworld.org/forum/showthread.php?650123-Multi-classing-as-good-as-it-seems
Recently there was a discussion here about the relative power of multiclassing vs. Single classes. The argument seemed to go in two directions. First, some observed that multiclassing is/is not overpowered. But a second vocal group suggested multiclassing is all wrong much of the time for RP reasons.
I have seen other such threads too. How can you have a paladin/warlock or a warlock/sorcerer or a warlock/cleric or a (fill in the blank). But most notably there seem to be more objections about clerics, warlock and paladins based on their supposed fealty to a particular being or cause.
I am wondering why the lore of spellcasters is so sacred to some? My own history suggests when I play a paladin, it is LG and really hews closely to AD&D ideals. If I play a cleric, I have been clear about religious affiliation as more than an afterthought. Never liked clerics without a power to pray to personally. But that is personal preference only! I can see cool concepts that deviate markedly as very valid.
So this leads me to ask: of all the things we home brew and change, why are these seemingly sacred cows so sacred to some? Do we think the RP aspect is a balancing factor in some way?
I observe that many who dislike multiclassing seem to dislike deviation from very traditional fluff elements in classes.
On one hand I get it and on another it seems rather limiting. I know when I play a warlock, I like to imagine them being taught magic but also exploring and learning on their own from hints given. I don't like the idea of spells being granted. I take arcana skill and don't enjoy sub 10 intelligence for any caster. Does it matter that much that we stick with fluff as written?
Last initial thought: many people seem to object to changing the fluff but also being inspired by some ability before a story. I have developed a number of concepts after flipping through the PHB and thinking an ability looks fun only then thinking about what kind of character would employ it. Admitting this may get me accused of ignoring fluff or not being traditional enough, I realize.
I don't necessarily dislike multiclassing, and have used it for decades. I'm not a fan of "dipping" or designing 20 levels of character with all of the multi-classing planned out before the character ever sees play either. The mechanical aspects of multiclassing can sometimes be a bit of a challenge. For example, 1st level characters get a bunch of things right away. Thematically, that makes sense. They've been training for several years for their new avocation. But taking it as a second class doesn't provide that. In 3/3.5e for example, you would be older when you gained 1st level in certain classes, since it theoretically took longer to learn them.
We treat the characters as real people in a real world. So if multiclassing fits their circumstance, that's great. We've altered the rules quite a bit, though. We have a number of feats that serve the purpose of a "dip" in that you can gain some of the key abilities without getting all of the benefits of a given class.
Now when it comes to certain classes, it's kind of simple for me. One of the things I love about D&D is the historical research it can send you on if you'd like. I prefer the world to have a very real late-medieval feel, because I think the mundane base makes the magic more fantastic. Religion played a very central place in the lives of medieval people. In a world where the gods are known to be real, may have actually walked the planet, and that they grant very real magic and abilities, I think they would be that more important. What separates a layman from a cleric or paladin? Faith. Much stronger faith, and a much stronger commitment. If you're dedicating your entire life to your deity to the degree that they are imbuing you with their power, why/how would you ever change? Would switching to a fighter be leading you on that path? If your worshipping a god of war, perhaps. And that makes sense. But if you're worshipping a god of peace, or nature, or knowledge, etc., not so much.
Switching to warlock, where you are making a pact with another being for power? I think that's a pretty good recipe for being an x-level ex-cleric/1st-level warlock. So for me, divine classes are more than just learning a vocation. They are about fully devoting your living being to their cause.
Really what it comes down to, is that if you are multiclassing out of a cleric or paladin, then there needs to be some good justification to make it work. If you can provide that, no problem, as long as you maintain the tenets of your deity. Multiclassing in is no problem as religious conversions are not only a thing, but desired by the deities.
Warlocks, on the other hand, are quite different. Yes, they are making a pact with another being. But that other being probably doesn't give a crap if you use that power or not. If it's the traditional "selling your soul to a fiend" approach, then hey, they own you whether you choose to utilize their power or not. So I don't really care if you multiclass from that.
I'm not really concerned about tradition. I'm concerned about engaging with the setting. If you have an interesting idea and it works within the setting, then I don't have an issue with it. If you do have ideas of what you want to do in the future, I don't really have a problem with that, but will recommend you try to not let those plans/expectations prevent your character from growing in a different direction if that seems appropriate. Many of us have had plans for our future, and yet find that we end up in very different places than we expected. I don't really forbid any specific combination, and expect that there will be some reason for it in the narrative of the character's life. But that has to fit with the setting as well.