ID is not as important as universe and address.
ID is used to organize fixtures, and rule of thumb...fixture groups start by groups of hundred.
Group 1 starting 101 for first fixture in group, fixture 2 in group 1 is 102 and so on.
Group 2 starting 201 and so on, but will not affect the patch
Each universe has 512 channels
Each fixture uses a certain amount of channels, to control functions separately each fixture will have its own address.
Each universe using DMX cable is not wired together, therefore important to match the addressing per universe.