PE to P Routing Redundancy

We have numerous PE routers coming back to one of our POPs with two ASR9K P routers. These PE routers are all single threaded fiber back to the pop so they can only land physically on one device at a time. We are planning to add a pair of Nexus 9K's in front of the ASR9K's for port aggregation. The N9K's are fully meshed with the ASR9K's for redundancy. I am now sorting out a clean method for establishing routing redundancy from the PE routers to each of the two P routers. The nexus are L2 only and our IGP is OSPF. Below are the current options we have come up with, but it feels like there should be a simpler method.

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1. Convert the PE-P links from /31 to /29 and setup multipoint/broadcast OSPF to each P router. Con:Waste lots of IP's
2. Create two VLANs on the PE routers with one VLAN going to each P router. /31's on both interfaces with OSPF. Con:Less wasted IP's but more complex and potential for loops.
3. HSRP on the P routers. Build OSPF from PE routers to HSRP primary IP on P router. Con: One P router will always be primary and difficult to load balance.
4. Make the Nexus L3 and bring up OSPF to the PE routers directly and OSPF up to the P routers. Con: Don't really want to add more hops in the path, but may be the most simple solution.

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Any thoughts or ideas would be appreciated!