Mostly you want quick, visual tricks with high impact that will leave them awestruck.
Right, which is why "Perfection" is a bad suggestion. It's neither visual nor quick.
I use a piece of rope, sponge balls and a set of 4" dia rings. That's all you need. I don't do cards because EVERYBODY has an uncle that showed them card tricks, just too common.
50% of my restaurant magic is card magic. Ambitious Card, Biddle Trick, Corner Card (my own), Bigger Finish, and several odd revelations - all great stuff.
I wish I knew enough rope magic to let it take up such a chunk of my work - then I could do that ring on a string routine I like more often.
How long should the effects be?
You need to fit an Opener, Bulk, and Closer into 3-5minutes.
Opener: As Jay Sankey says, "Within 5 seconds of you approaching a table, there better be magic." The opener must be extremely visual, fast, and hopefully lead you into your next effect.
Bulk: Whatever you want to do, this is where you get to be funny and charming so make the most of it. Many magicians advise using a "sequence of 3" within the Bulk area. ie: you can do an ACR with 2 reveals, then Card to wallet (1,2,3). You can do several sequences of 3 as long as they all go "something, something, climax".
Closer: This is your farewell to your guests. It should be hardhitting, but not as flashy. The point is not to make them go WOW!, it's to make them miss you.