I think you can do that in a live situation pretty comfy.
The main focus point on Elektron hardware is the following:
a Pattern is an entity related to a Kit slot.
If you “load” a pattern (e.g. A05) you have already it saved in that position related to a specific Kit.
You can start tweaking…once you are satisfied, Copy it and paste it to , say, A06. Save this position too.
Jump back to A05 and reload the Pattern (NO+PATTERN on minikey).
You have now 2 versions (patterns).
They are both related to the same kit. If you alter things (e.g. Filter Cutoff on T2 and T4) on A06, those will happen on same tracks on Pattern A05.
NOW
you should make a choice:
• leaving the 2 patterns sharing the same kit;
• copying the kit to a new slot and starting to have two independent entities.
Stick also with the idea of WHAT is related to Pattern-entity and Kit-entity.
For example the Arpeggiator settings are saved within the Pattern-entity.
While Performance Page is saved within a Kit.
In a Live situation the Pattern-reload is your friend…because you have a saved state, right?
So you can start tweaking things following your inspiration…then you can jump back to saved state hitting the combo (NO+PATTERN).
You can also keep growing the live-flow by copy/paste Patterns onto new slots.
Keep in mind the pasting action is not immediate (you will loose some steps at the beggining of the new pattern)…but this will not mess up things too much…for me =)