add controls to already generated meta rig I saw some answers to similar question here, but either it doesn't match my needs or I did not understand them.

Long story short: I didn't change rigify type on the fingers to super_finger but I already did the weight repaint job and generated the rig. Do I have to redo the whole thing? Is this losted hours of work?

full story:
My problem is I have an already generated metarig. I did aaaaall the weight paint corrections (there was a lot because I added few custom bones to the original armature, like a bag, some swords etc) But when I started animating, I noticed there was no controls for the fingers (you know, the lines you select and scale to retract fingers) I found out on stackexchange that I should change the rigify type on those fingers to super_finger instead of tentacles. Do I have to regenerated the whole thing and redo the whole weight repaint job again?

Thank you
The weights are properties of the vertex groups, so they belong to the mesh object, no matter which rig you use. They get overwritten only if you perform an automatic weighting or a "with empty group" option. 

So you can create the new rig and parent it to the mesh using the simple "Armature deform" option.

The names of the new rig bones should be the same as the old, so everithing should work fine (except for the new fingers bones, of course).

Later you can also perform an automtic weghting limited to the new fingers bones, to have a good starting point to be refined with weight painting or direct weight assign.