I want to give you my personal opinion because I have considered the same thing as well. I do not want to be anything but honest. You already know that I admire your work so do not think my opinions are based on your quality or design. This is what I would tell anyone that asked me to evaluate a business plan that included disc dying.
First, I have came to the conclusion that the majority of people that play with dyed discs, dyed them themselves for their own use. I feel that most people think that a dyed disc is sort of like a model car. Most people say "check out the model car I made" but will rarely say "look at the mode car I purchased". This is not to say that people do not appreciate the work that goes into the construction of the model when they are viewing it. I have never thought about it before just now, but I guess Disc Dying is also similar to car customization. Some will pay for the finished product but many more enjoy the doing the work themselves. Most will not be willing to pay what it is worth after completion.
I have thought the different methods to make money dyeing. I honestly did not see a way to make any money with any known method. I know a lot of hard work goes into dyes because of the labor. Even If you were ever to defy the odds and make some money, you potentially could run into licensing issues with Marvel, DC, or whose ever likenesses where being borrowed at the time. Also you would have to be a mind reader. For example, if a customer is a Yankees fan, they might not want your Yankees dye because it is on a Wraith instead of a Destroyer. Even if you can find the buyer that would pay for a certain dye on a certain disc, you would also have to get the right weight that they wanted. It would be very difficult to find your buyer.
I assumed the best methods to make money and find the buyer would be to..
1. Make dyes that are specific to the discs. (the Flash symbol on a Flash or the Godfather on a Boss ect.) Again if you ever were to make serious money, you more than likely would eventually get a cease and desist letter forcing you to stop, especially if you were selling on Ebay.
2. Commission work. I would be very afraid to do this one because if you get a little bleed you will have an unsatisfied customer and no one else will be willing to buy a less than perfect dye with someone else kids on it. Also because you do not have a finished product to show the customer they would not know what they are getting before they purchase and being that that it is on a 15 dollar disc, your percentage loss would not make it worth it even if you were willing to sell it for 40.00. Logo makers will provide multiple proofs and obviously you would have to be perfect on the first try.
3. The third and most risky would be to commemorate special discs with symbols or messages. For example you could do a really nice Ace of Spades on someones first ace disc or any other custom message to a special disc. This would be a huge risk because a dye would eventually go bad and damage a non replaceable disc.
4. The forth would be to do work in quantity to spread out the cost of misprints but the availability of Innova custom stamps and Discraft full color discs would not make this advantageous to the buyer to pay what would make it worth it for you.
The only real opportunity I could come up with was to choose a symbol that (1)would be universally accepted by a large group of disc golfers yet (2) still provide the uniqueness of a custom disc while (3) not infringing on any licensing issues. I also though (4) it should be a dye that would not be ruined with bleeding issues. Unfortunately, the only thing that I felt met that criteria was a pot leaf and making those for profit were just not for me.
I thought a lot about it and I honestly do not think you or anyone else would ever be able to sell enough to make it financially worth it.
I do think that selling discs would at best provide you with the funds to buy more discs and Rit to continue to break even in an enjoyable hobby.
My honest evaluation would be you will not be able to get the financial rewards of dyeing discs but if you really enjoy it you can reach the reward of having a hobby that can pay for itself. If this is the reward you would be will to receive then go for it but I would not expect much financial gain.
OMG, bro, you really need to hurry! 
