Here in Omni 1:17, Oliver Cowdery initially wrote “they had had wars and serious contentions”. Considerably later, with heavier and darker ink flow (and with a duller quill), Oliver supralinearly inserted many before wars. Like many corrections Oliver made on pages 113 and 114 of 𝓟, the ink flow is clearly different:
All these corrections appear to have been made while proofing 𝓟 against 𝓞. See the discussion under each case.
Elsewhere in the text, there are 30 places where war(s) and contention(s) are conjoined. And two of these have much or many modifying war(s), as in Omni 1:17:
The critical text will therefore maintain the many that Oliver Cowdery later inserted before wars in Omni 1:17.
Summary: Retain Oliver Cowdery’s correction to the printer’s manuscript in Omni 1:17 (“many wars and serious contentions”).