The encounter building rules in XGTE are easier to use than the DMG rules, and handle variable party size and mixed CR foes more sensibly, but they have the problem that they're tuned for medium encounters (medium-hard for solos). However, analyzing the DMG rules, it appears that the number scaling for monsters is approximately 1.5 power (sensible; Lanchester's laws give a quadratic scaling if all figures are able to engage and are using single target attacks; area effects and choke points reduce the scaling, which means it's fairly straightforward to work out adjustments:
First, we should unify the 'solo monster' scale (which is roughly Hard) with the Multiple Monsters scale. I suggest that a 4-PC solo is 1:6, a 5-PC solo is 1:7, a 6-PC is 1:8. This allows us to have an effective party size -- which is the party size we use to design encounters.
If you run 6 encounters per day, total budget is 6*party size, with not more than 1.5*party size on any one encounter.
If you run 3 encounters per day, total budget is 5*party size, with not more than 2*party size on any one encounter.
If you run 2 encounters per day, total budget is 4*party size, with not more than 2.5*party size on any one encounter.
If you run 1 encounter per day, total budget is 3*party size (this is only about 85% of budget, but not getting short rests does have a cost).
Thus, for 4 PCs at level 14 and one encounter per day (to use an example from the thread that inspired me), budget is 12 points. A CR 16 Marilith is 6 points, a CR 12 Archmage is 4 points, so you have 2 points left to throw in an additional CR 8 or so monster.
The encounter building rules in XGTE are easier to use than the DMG rules, and handle variable party size and mixed CR foes more sensibly, but they have the problem that they're tuned for medium encounters (medium-hard for solos). However, analyzing the DMG rules, it appears that the number scaling for monsters is approximately 1.5 power (sensible; Lanchester's laws give a quadratic scaling if all figures are able to engage and are using single target attacks; area effects and choke points reduce the scaling, which means it's fairly straightforward to work out adjustments:
First, we should unify the 'solo monster' scale (which is roughly Hard) with the Multiple Monsters scale. I suggest that a 4-PC solo is 1:6, a 5-PC solo is 1:7, a 6-PC is 1:8. This allows us to have an effective party size -- which is the party size we use to design encounters.
Thus, for 4 PCs at level 14 and one encounter per day (to use an example from the thread that inspired me), budget is 12 points. A CR 16 Marilith is 6 points, a CR 12 Archmage is 4 points, so you have 2 points left to throw in an additional CR 8 or so monster.