My wife and I Just spent a weeks vacation at Laguna Beach and had our ST1300 with us. We did sample some of those roads. Ortega highway is good ride but can be a bit busy and many motorist have NOT learned how to use turnouts. Here is a picture of Lake Elsinore from the lookout on HWY 74.
But you you do have some gems. HWY 243 through Idylwild over to Banning is fantastic,we loved it! The road and the views are great. And HWY 74 Pines to Palms is superb as well. Some of the sections east of Hemet remind me of our HWY 299 West out of Redding,Buckhorn summit...good stuff! Anyone visiting southern California those two roads(243 & 74) are a must ride.