Access is pretty easy, they’re in every canal from the middle of Miami south. Most ponds that way will hold them as well.
As long as you don’t come right after a cold front, they’re pretty easy. 3” live shiners or jerk baits worked as fast as you can will catch them. They tend to show themselves within a few casts if they are in the location, if not just keep moving.
Cover as much hard structure as you can, once you find them you’ll catch several back to back. Once the bite dies, keep covering water.
As for largemouth, if you’re catching peacocks you may be around smaller largemouth (and potentially snook and tarpon) but you’ll want to go several hours north to get into the best largemouth fishing Florida offers.
Same deal with the flats, I’m not aware of much in terms of wade able flats as far south as you need to be for peacocks. You’d either need to get a guide or go several hours north for DIY wading.
If you go the diy route, flats fishing is pretty straightforward if you are a good bass fisherman. If there’s no grass or oysters, I wouldn’t waste my time on a flat. Tides control everything, no moving water no fish.
Low tide is when you’re searching for tailing reds with shrimp/crab imitations. Rising mid to high, follow the current up looking for structure and eventually you’ll be skipping mangroves when it’s all the way up. Swim baits and flukes are the way to go with higher water.
Peacocks don’t care what time of day you go, lmb timing depends on weather, flats is pretty much a right at sunup deal. Typically need to be wading by 5:30 AM at the latest, bite is almost always over with by 8:30 AM, everything after that is a waste of time.