The key to the Miser's Dream is not necessarily the patter, but the presentation. Where are the coins being produced from? If you produce them one after another from behind children's ears I will hunt you down and force you to watch Barney videos for 48 hours straight so that you have a sense of how your audience would feel watching that presentation.
Look at the Routines in Bobo's Modern Coin Magic. Also, check out Charlie Miller's routine (Genii, July 1965). Jeff McBride and Levant have great routines that you can see on YouTube. Don't copy any of those, but use them for inspiration.
After you get some ideas of how to produce the coins, you will get a sense of the routine. Does it feel serious, funny, awkward or mystical to you?
Think about the justification. Why are you pulling coins out of the air? Because you can, isn't a good answer.
Think about what you want to convey with the effect. There are a lot of themes that can go with the effect. Some serious, some whimsical.
Think about how this fits into your show. Are there other effects before it or after it? Can the patter you use transition the routine from another effect or from it into another effect?
My advice is to write out different methods of producing the coins. Then brainstorm by listing 20 words that relate to the effect. That will give you a sense of what your audience will associate with the effect. If you tie your patter to one of those works, it will make your patter stronger.
