Initiative plays a key role in how well saves work in 5E. Since Delay no longer exists (except as a house rule), PC spell casters can be at a disadvantage when it comes to save spells based on initiative.
Example initiative order:
PC 1
NPC 1
PC 2
NPC 2
PC 3
NPC 3
PC Spellcaster
NPC BBEG
Say that the PC Spellcaster wants to cast a Hold Person spell on the NPC BBEG.
The NPC BBEG gets a save on the PC Spellcaster's turn, then if necessary, gets another save at the end of his own turn.
This results in the following odds, say at level 3 when the PC has a save DC of 13 and the BBEG has a +0 on his saves:
If the spell caster cast the spell on NPC 3 with a +0 to saves:
As can be seen, the results here vary significantly based on initiative. Without Delay, spell casters cannot do much to affect this situation. Course, using Delay means that the BBEG would be able to get one action in automatically before the caster could cast, but the player does not even have the option to take that risk.
Example initiative order:
PC 1
NPC 1
PC 2
NPC 2
PC 3
NPC 3
PC Spellcaster
NPC BBEG
Say that the PC Spellcaster wants to cast a Hold Person spell on the NPC BBEG.
The NPC BBEG gets a save on the PC Spellcaster's turn, then if necessary, gets another save at the end of his own turn.
This results in the following odds, say at level 3 when the PC has a save DC of 13 and the BBEG has a +0 on his saves:
Code:
40%: nothing happens
24%: loses an action, no paralysis.
14%: loses two actions and one full round of paralysis.
09%: loses three actions and two full rounds of paralysis.
05%: loses four actions and three full rounds of paralysis.
If the spell caster cast the spell on NPC 3 with a +0 to saves:
Code:
40%: nothing happens
24%: loses an action and one full round of paralysis.
14%: loses two actions and two full rounds of paralysis.
09%: loses three actions and three full rounds of paralysis.
05%: loses four actions and four full rounds of paralysis.
As can be seen, the results here vary significantly based on initiative. Without Delay, spell casters cannot do much to affect this situation. Course, using Delay means that the BBEG would be able to get one action in automatically before the caster could cast, but the player does not even have the option to take that risk.