I'm curious how common resurrection is assumed to be. Out of every N deaths, how often can characters expect to be raised? Does it vary for you by tier?
N
Keyword "can." It's ALWAYS possible, no matter the level.
My campaign is built so any character can be brought back. Characters can also change class if they want. Or pretty much whatever.
Players (usually) invest some time and energy in their character. IME, they generally try to make reasoned or in-character decisions, either for color, or for survival, or both. When they hit 6th level, its quite a let-down to die, let alone have to start from square one, and in the groups I play in, its cheesy to just roll up a high-level character they didn't have to "work" for.
(Class changes are a serious matter, but still possible. The lower level you are, the easier such an endeavor might be. The biggest issue is that if you haven't "worked" for your class, it's likely you won't know how to maximize your potential at higher levels of ability.)
Anyway, we decided early on that for my campaign, almost anything was possible.
For a price.
And we're not talking just gold.
Internal consistency and RAW are important. We discuss options when a character is in a tight spot.
The player ALWAYS has a choice. Come back RIGHT NOW, and experience Consequence A. Roll up a temporary character or play an NPC until you can be brought back at a more opportune moment, and experience Consequence B. Have a party member bring you back and experience Consequence C.
Not everything is perfectly laid out, but the general parameters are clear enough.
For example, a player had their warlock PC keep the entire party alive through what was going to kill several characters, including the warlock. As a result, the patron infused some of its essence into the warlock to give him enough power to keep the party alive by passing through the patron's native habitat -- normally not survivable for the PCs. From that point on, the patron could spy on ANYTHING the warlock did, and manipulate events in its direction.
It's very difficult to juggle an evil patron and party loyalties. Sooner or later something's going to give. And the stronger the hold the patron has on you...