EMB FO is very junior everywhere (assuming there is movement so people can transition to the jet). PDX or SLC are unlikely initially, but possible within a few months (again assuming movement)

Line might pay 50-10 hours more than reserve, plus per diem which does add up if you bring all your own food.

Per diem depends on the type of trips you fly. It's $1.65 per hour of duty, so four locals with nine duty hours each would pay $59. A typical four day would be about 78 hours duty so that would pay $128. Either way you'd credit about 20 hours that week, but there's big difference in per diem.