Award tickets are refundable; there is a $150 fee to redeposit the miles ($25 for the second award going back to the same account); this is only waived for Executive Platinum. But date and time changes are free for anyone, so those tickets could be used another time for no fee, as long as it's the same origin/destination.

There's no status benefit for cancelling the paid tickets on the outbound. The change fee is probably $200 each, so you would have a voucher for $37 that you could use in the future. You just most likely have to contact AA to cancel the reservation before departure time.

Each ticket can be handled independently. But if the OP is flying without his wife, he won't get any of her status benefits.