GCP -
Sorry to hear about the break-in. I also have a remote property that is a not always occupied, so I know the feeling of being worried about your place/stuff why you are away.
I don't have the ability to post pictures right now, but here are some of the things I have done on my gate/entrance.
First, get yourself a better chain and lock. With portable grinders/etc, I thief can still cut about anything, but you want to make it as tough as possible (or have them have to stand at your gate for longer than they may want to).
I use the following chain and lock on my front gate. It is not cheap, but it is cheaper than the stuff behind the gate.
Kryptonite New York Fahgettaboudit Chain with Disc Lock - Street Motorcycle - Motorcycle Superstore
Second, I also use a security camera near the gate. Place it BEHIND the gate, where it can still be seen, but high enough up on a pole or tree so that someone would need a ladder to reach-it. (Not stand on a truck hood and steal it).
I did not have power at my gate, so I was required to get a camera that would email me a picture (via cell service) when it detects motion. You will get a lot of pictures of deer/etc, but you will also get pictures of anyone near your gate.
I went with this camera setup. It also is not cheap, but I was limited to available choices given my location and lack of power/etc at the property entrance. Mine is installed about 20 yards behind the gate up in a tree. You don't want to hide it. You want it to be seen as a detterent.
https://www.smartscouter.com/ssDefault.aspx
Once you install the camera, get a sign that states the property is under surveillance. I went with the biggest one I could find.
Property Protected by Video Surveillance Sign - No Trespassing, SKU: K-2257
I then installed cheaper security cameras on my property porch (watching the front door) and my workshop. These cameras were just basic web-cams. I was able to do this because I have power and a network/wireless connection at these locations. These cameras also email me a picture on any motion. These cameras cost under a 100 bucks each.
I also gave the local law enforcement a donation and asked them to drive by my property fairly regularly and light it up with the spotlight. They actually have been pretty good about doing this.
I have not had to resort to this extreme, but my neighbor dug a 6 foot wide trench behind his gate with a center cement cross support. The trench is about 4 feet deep. When he is home a large piece of plate steel covers the trench so he can drive over it. When he leaves, he uses his tractor to slide it back off the trench. This creates a gap in his driveway that is impossible to cross with a vehicle. His driveway is setup so that this is the only way to advance up his property.
The downside to this approach is that he has to leave his car at the gate when he returns and go get the tractor to push the plate back over the trench before he can drive his car up to the house.
Hope these ideas help.