I'm running a Birthright campaign, and in the original rules I noticed that spells like raise dead and resurrection were "discouraged". The setting features rules for letting PC's be regents of domains, rulers of kingdoms, and it made sense in that when a ruler is killed, bringing them back is anticlimactic, and troublesome for certain types of adventures. For my 5e conversion, I just ruled that spells that bring people back from the dead do not exist. My rule for new characters is they start at 1st level, no matter what the party is at; as they will quickly catch up. I'm fairly generous with magic items and gold, but definitely not monty haul. I don't fudge die rolls. I state all of this to give people an idea of context. I'm not a killer DM, despite all of this, PC death is rare, even so far in 5e.
My thinking:
- At low levels it doesn't matter. You're going to stay dead if you die in most campaigns anyway, unless the DM is nice and has a high level NPC do you a favor, and most players are not so attached to lower level characters anyway.
- At higher levels, it will change the game. Players are forced to be more conservative. As DM, I will be forced to be more careful with adventure design and not cause an unfair TPK.
- I am less likely to use save or die effects against them. I don't want a single bad die roll to kill them too arbitrarily. It could happen regardless. And I will use them sometimes.
My players are fine with all of this, but it does add a level of dramatic tension to the game, and curbs their tendency to charge in and try to kill everything. That's what I'm going for, so I'm happy with it. When a PC will die, it will mean something, and I try to design every difficult encounter with some aspect of heroism involved so that if they do perish, it will be a fitting end, and not something like a random wandering monster that cannot be escaped or negotiated with.
Here is the thing: At higher levels, when they do have a lot invested in their characters, I can change my mind. It's easy to bring raise dead spells back if I want. I create an adventure for them that enables the casting of such spells; perhaps an important NPC dies and they find a way to open the portals to the realm of the dead, and those spells become available in the campaign. Or a PC dies and they travel to the realm of the dead itself to retrieve their soul. It's easy to bring that stuff back. It's hard to get rid of it once you add it.
That's just my thinking. I don't see anything wrong with adding some additional cost or side effect to these spells if that's the way you want to handle it, or using the RAW, but I do think all DM's should think about it and decide what to do before starting their campaigns.