I have lived briefly in the Redhawk area of Temecula, and now live in Murrieta.
I like both areas, but between the two Temecula has better city government. Both areas have great schools though.
I would look in the more established areas of Temecula around Hwy 79 and also the better parts of Murrieta.
French Valley? A definite no for me. The traffic and access problems, not to mention the issues created by too much development too fast have put me off that area.