Plantation resident here. I've lived in Miami all of my life and moved to Broward in Oct. of 2017.
Coaches - none that are really great. Maybe try Mike Ward, former UM coach and coached a few years while I was on the team for FIU. Definitely try to get in contact with Spencer West for for the in's and out's of Fort Lauderdale running. There are a couple 2:5X women in the SoFlo area - Ana Maria Villegas and Andrea Hunter Cadavid.
Places to run - as you mentioned, Vista View is a good option. You can also run
-Markham Park not too far from Vista, which has a 20+ mile gravel levee loop parallel to the park overlooking the everglades (beautiful run during sunset). When it gets dark later, this is one of my go to runs, but be warned there are no bathrooms, water fountains, or shade on the levee. Markham park itself has plenty of bathrooms and places to run.
-Weston - there are a lot of bike paths in the area where you can get good mileage without looping a lot. If you start in Weston Town Center, you can make a 7.5 mile actual loop going down Bonaventure Blvd towards South Post Road, head west towards Saddle Club Road, and then back north towards Royal Palm Blvd. I ran my last Houston Half Marathon workout here last night. Great place for tempos/tempo repeats since it's flat and has good footing. Just be aware of the cyclist as some getting crabby about running on the bike path. You can also start in Weston Town Center and run to Vista View Park (about 5.5 miles to get there), run some loops in Vista, and head back.
-Hiatus Road Greenway (I ran this loop this morning). 6-mile asphalt bike bath, although, you can run on the grass next to the path. There are no bathrooms or water fountains, but there are shopping plazas in the beginning of the trail. You can also mix this loop with New River Greenway (11 miles long), which intersects at the end of Hiatus. These are my go to loops since I can run right out of the house to them.
-A1A (you seem to be familiar with this trail already).
There are a bunch of other places I can recommend to run, especially in the Miami area. Unfortunately, I don't know of too many good coaches I would recommend outside the high school circuit that would be of assistance, especially for the marathon.