Cisco Switching/Routing :: 3640 GLBP Working Now Want Interface Redundancy?

So I have 2 routers (cisco 3640) that each go to their own ISP and then back to the same switch.  I have setup ospf and glbp, and now have pretty good redundancy.  If either internet connection or routers go down everything is still golden. 
 
So I was thinking that if an interface went down then the router would not be load balanced with glbp which got me thinking whats the best way to get interface redundancy (and I was going to add a 2nd switch with the second interface).

1) Setup BVI on the 2 interfaces.
2) Setup a 2nd interfaces (on each router), I would have to split the subnet, for instance: [code]then the machines could be on the subnet 192.168.0. 0/23 and setup glbp for 1 ip across all 4 interfaces (I'm not even sure if you can do this but think it would work).
3) Is there a way to utilize etherchannel or anything like this
 
A negative to option 2 would be that if 1 of the interfaces went down, all the sudden 2/3 (or so) of your traffic would be going through 1 router.