Legacy or Dynamic Tables

I have started making tables that have an internal logic of escalation or change. As choices are rolled, they are struck off, exposing new options. The same type of die is used throughout. For example, a D6 encounter chart could look as follows:

1 Skeleton

2 Skeleton Gang

3 Zombie

4 Ghoul

5 Zombie Gang

6 Ghoul Gang

7 Shadow

8 Wight

9 Mummy

During their first pass through the tomb, the Shadow, Wight, and Mummy cannot be encountered. However, a random encounter reveals a roll of 4, the Ghoul. The Ghoul is dispatched and now the chart looks as follows:

1 Skeleton

2 Skeleton Gang

3 Zombie

4 Zombie Gang

5 Ghoul Gang

6 Shadow

7 Wight

8 Mummy

In their next trip through the tomb, the adventurers run a slightly greater risk, has the Shadow is now a possibility. The greater risk is telegraphed to the players through environmental or other clues, so they know what might be afoot. A 5 is rolled, and our heroes struggle with the gang of Ghouls. After returning to the village for the night, they return, refreshed. But the dynamic is changed. The chart looks like this:

1 Skeleton

2 Skeleton Gang

3 Zombie

4 Zombie Gang

5  Shadow

6 Wight

7 Mummy

This is obviously an extreme example of escalation, but it builds in the ways interlopers can change the environment through their presence and actions. The items on the lower part of the chart can be positive, or they could be changes in the physical structure. Does the very fabric of the tomb become looser, with greater risks of walls falling? Does the dispatching of the undead create an opportunity for forces of good to appear? It can be a built in timer, so that after a set number of encounters, there is a greater chance of a particular event happening.

Turning my list of possibilities into an evolving chart of realities makes locations more dynamic, and it also forces me out of dictating what that dynamism looks like. Not every thing is going to happen. The only thing I know is the general trajectory (eg 'The more the heroes interfere in the situation, the more arcane forces will be unleashed') but not how it is going to play out at the table. If the Mummy is the most powerful creature in the tomb, it might appear much earlier than I anticipate, forcing the players to change their own plans, try different tactics, and avoid the monster they unleashed until they are ready, and also putting me into a new place. Or it might appear later. What is it waiting for?