1) I don't know what the political situation is between US & Pakistan. But keeping the F-16 line open is always in everybody's interest.
2) UAE has no issues in PAF getting the Blk61.
3) Sir, Please understand, it's our royalties, it comes to us, so we decide, who pays, how much. Royalties might be lowered or even waived. Not sure what the situation might be today.
4) F16-V is a very good option, but taking the nuclear angle into account, a few squadrons, 2 or 3, of Blk61, which have in built EMP shielding will definitely go a long way in offering a credible defence & offensive capability to Pakistan.