I'd say it depends on how much time you have, what you like to do, and how much driving you want to do.  When we have out of town visitors, we always take them to St. Augustine, and usually someplace like Little Talbot Island State Park.  Closer in are the beaches (Jax Beach, Atlantic Beach, Ponte Vedra).   

Here's an idea for a one-day road trip.  Take I-95 South to Butler Blvd., turn east on Butler Blvd and at the end of Butler turn south on A1A.  Park at Mickler's Landing to see Ponte Vedra Beach.  Keep going south on A1A and you'll get to St. Augustine.  In St. Augustine visit the fort and historic district.  I ate at Harry's in St. Augustine the other day and I thought it was very good.  

If you want just one day at a beach, my favorite is Little Talbot Island State Park.  Take your lunch with you.  It is totally undeveloped.  If you park in the main parking lot and walk north on the beach, it is wilderness.  No hotels, no houses, no nothing.  Just a deserted stretch of beach.  If you walk half a mile to the north, you will leave all the people behind, and it'll be like you're the last person on earth.  Obviously, I really like it.  

Others in this thread have had some good suggestions- TopGolf is fun.  If you like real golf there are a lot of golf courses.

Things are really spread out around here.  You need to look at a map.

One last thing to note: they don't take cash for anything at a Jaguar game.  And if you want to park and take the stadium shuttle, you have to download an app and pre-pay the $8 for the shuttle.  The app is called Token Transit.  You prepay and show the QR code on your phone to get on the shuttle.  There are various shuttle locations around town.  If you want more specific details, just ask.

I keep coming back and adding to this post, but here's another thing: as far as where to sit in the stadium, after many years of experience, I think if you don't want to pay big money for a club seat, the best bang for your buck is in the South-West corner of the stadium, but not in the upper deck.  Like section 201, 202, 203.  Reason being, the sun goes down BEHIND you. 

Damn, I keep coming back and writing more, but here's something else- if you're staying in the South-West side of town, and you want to play golf, try Eagle Landing.  It's cheap, it's usually in really good shape, and it's one of my favorites.  You would need to make a tee time a week in advance, though.

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