@Blackwolfz, as a fellow South Floridian (within Palm Beach), I can say that you absolutely should use the Flex daily schedule. Granted you will not get the most out of it, without upgrading your valve setup, but it will still be much better than a simple time based schedule.
The trick is to setup all of your zones (how ever many your index valve has) with identical parameters, perhaps based on one of your zones where the plants have the shallowest roots. Flex daily setup this way may technically water some zones more than they should be, but it will not be worse than a simple time based schedule.
In order for the system to work with your index valve, do not forget to setup your master valve setting to the Well / Pump mode, this way the system will allow you to add an automatic pause between zones in order to allow your index valve to switch over to the next one.
Should you fail to find a suitable weather station within Rachio interface, check out weatherunderground.com, I’ve wrote a while back on how to find (link) a station with good rainfall data. Let me know via reply here or a PM (link) and I can help you to set it up to be usable with your Gen 2 rachio.
Cheers,
Gene