I haven’t done serrated tabs - but @evansd2’s post on using the clone function in Inkscape may be what you need to look into. Make one serrated tab and clone it, and then use the clone to make the rest…
For the leather holes I ran across this method recently and have found it to be ab fab for easily making holes and then moving them if I need to:
Just beneath that post I added a slight modification that I do specifically for leather holes - so read at least those two 
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