Like I said above, we're in Mandarin and close to shopping (St. Johns TC, San Marco, and only 15 min from OP). The area over here is built up: Publix, Kohls, numerous eating places with-in 5 minutes but it's not so built up like the Blanding area. We can get to the beach in about 20-30 min on a good day. Base is opposite of traffic and takes the hubby 15-20 minutes and the only traffic he hits is on 17, which is the same traffic those who live in Eagle Harbor/OP hit coming up to base.
I feel safe enough to walk around in the evenings in my neighborhood by myself, and I go biking around the area alone as well without any weird feeling.
The reason we chose this area was because we wanted something different. We lived on base overseas and really wanted to separate ourselves a little bit. We looked in the Avondale/Riverside area but for what we wanted to spend on a house we couldn't get the amenities that a "newer" house would provide, and we did look in the area quite a bit.
We just moved here in December and we like it (except for the FL summer now

). I like the fact that Jax is a big little city.
There are some new builds, condos, not as new homes and apartments in the area we're in which is around Bartram Park so a good smattering of choices if you're not quite sure what you want.
I'd drive around each area at different times of the day and look at the homes, prices, and local amenities to decide...everyone is going to have their favorite area, which obviously may not work for you.
Good luck!