Just changing "peace" to "pace" you lose me.
Leigh is fine on its own but it really loses any appeal for me when it is grafted onto the end of another name. So Paceigh is a non-starter for me, sorry.
In addition to the excellent suggestions you've already gotten, how about these names that mean "peace:"
MiraPacifica (could be a fun GP mn)
Pax /
PazShalom /
Salome ("sah-LO-may") /
Salomea ("sahl-uh-MAY-uh")
Jemima (= dove)
Paloma /
Columba / Colombine (= dove)