I don't agree with the comment about making a bigger deal out of doing an ace "production" - it wouldn't add to the trick, but rather be viewed by the audience as a totally seperate event. Of course, there's nothing wrong with that, but it's not relevant to how good the tricks on show were.
Obviously, both tricks are playing with the same principles - which are very strong. You may incidentally want to check out John Guastaferro's "Famous Aces" for some similar ideas (Second Storm DVDs). I suspect I know your method, and I think you'd get some interesting ideas off John G's work.
In each trick the effect is clear. "Joker On You" is very nice, however it feels a little laboured, especially without knowing what your patter and presentation is like. Just a thought, you could use some concepts from "Be Honest, What Is It" (AKA "2 card monte") to get through the effect a little more cleanly. This approach also has the benefit of spectator involvement.
"Mirage" - big comment here. I don't like the show of the empty box right before you pull the card out of it. I understand the temptation to, but it doesn't work for me. One thing I've started taking into account in my own work is this:
Just because you can, doesn't mean that you should.
Others may disagree. On perhaps a less personal note, this trick suffers from the classic problem of all "selection vanishes from the deck" tricks - you have to show the whole deck to prove your point, which is a drag. Try vanishing the card from a small packet - there are numerous gaff-free methods to do this of course. You could have fun with an extra phase - the card vanishes from the packet, appears reversed in the deck (the venerable "Biddle Trick"). You say you're going to reverse the process, and make the card vanish from the deck using any number of methods - colour change, tent vanish, rub a dub, double lift - but it fails to appear in the packet. You missed - it ends up in the card box!
Joker On You has potential I think. Mirage feels like you're using a boulder to crush an ant. Some very interesting thoughts which I think you can refine into great tricks.