park these miles in DL and be done with it. DL miles never expire, the risk is pretty minimal, and honestly DL miles (though creeping ever higher redemption rates) are more useful day to day than AS miles IMO.

you can get a low level F one way for 45K domestically, or next tier is 55K. there are a few hidden gem routes out there with very good availability at those prices, some with a dumbed down D1 product.