Please allow for a range of items rather than just a single item.

example:

1 bit: one command
2-5 bits: a different command
6 bits: another command
7-10 bits: another different command

Same for gifted subs.

If I understood you correctly, what you proposed is already doable in v2.0 and higher.
The plugin will react to an event if the amount (cheered bits, gifted subs...) is equal or higher than what you set (just taking the highest reward that has been reached). Which means that if you set your config like this you will get the expected result:

CHEER_REWARDS:
  1:
    - one command
  2:
    - a different command
  6:
    - another command
  7:
    - another different command

Let's say that you get cheered 4 bits, which would be in the range of 2-5 bits. As the plugin will take into account the highest amount reached "another command" will be executed, because is higher than 2 bits but won't run any other command because it didn't reach the next reward (6 bits).