It helps a bit (way low resolution), but quite honestly without seeing the actual in-game node placements, weapon lockers and vehicle loadouts this is still mostly a guess on my part for what links will work here. Here are two possibilities:
templinks #1

templinks #2

#2 is the better of the two choices but I will stress again that without seeing them in action on an actual map I have no idea if they really work or not.
My thinking at the moment is to place another node in between the long path that goes from the two nodes at the far edges of the map in the upper left and lower left corners. If you're keeping the tunnel nodes, I can see them being used as locked safes as they are both protected and positioned fairly well for that task.
The new blue core primary that is down and to the right of that core in your image is too close to the levi node btw. Both it and the new red primary (to a lesser degree but it is still an issue) need to be closer to their respective cores to put some distance from both the center and levi nodes.
EDIT -> Here is what my current thinking is on links/new nodes is. Figured a picture might help out.
newlinks

The big red dot at middle left of the shot is where I envision a new node linking into the rest as you can see. It would be placed in the middle of the path that takes you between the two outside nodes that I talked about above. Still need to move the core nodes as I mentioned but this will hopefully show you a more specific idea of what I think needs to be done.