Only if you are unhappy with the performance you are getting on the server attached to node 2.
Of course the better answer down the line will be to get a switch, but until then, if you are ok with the performance on ESX2 going over the interconnect, then don't do anything.
If you are experiencing performance issues than you have a few options.
1. Connect ESX2 to FAS1
2. Get a switch so that ESX2 can connect to either
3. Move the LUNs that ESX2 uses over to FAS2.
But, again, if you are happy with the performance on ESX2, you don't have to do anything.