Developing wordpress plugin, need advice

I would say definitely go with some form of activation for sure - important to protect your hard work!
I think pretty well all the quality paid plugins I use require some form of activation - not sure if I've ever had to actually visit the home website to register though. I usually receive an activation code via email and simply enter it on the settings page for the plugin.

At least one or two plugins of mine can only only be used on a single domain - no clue how this is monitored on their end, but it certainly works! lol (for one of them I didn't even realize it was a single domain license until I tried installing it on another site).

Not sure if this addresses what you are asking. Feel free to elaborate.

B

Here is something to consider...

You might want to have some of the most crucial functions hosted on your own server. That way people who pirate your plugin won't be able to use it.

In other words, create an API and use the plugin to access it.

This is something I've started introducing in my products.

If you are going to put it on Clickbank you should write code into the plugin that will enable you to deactivate it if they ask for a refund. I have my software coded so if someone decides to do a charge back, I simply go into my server and redirect the code to open a new page with a nasty message after they try to pull a fast one on me.

sounds interesting, there are a number of options, but it is not as easy to do it, as it is to say it, there really is no 100 percent, perfect method to stop someone from gaining access to your product, but that does not mean that you should not actively try to slow down those that would steal your products.

These days, you simply have to manage your products, because if you do not then you are doing your paying customers a dis service, after all when a customer makes a purchase of a product, it is really up to the seller to protect them from others that do not pay for the product,

I recently had a discussion with a seller that refused to even discuss protecting their products, they just did not care that people were giving away their products all over the internet, (when I asked this warrior what about all the paying customers out there do they not deserve to be able to access a product that stays competitive for a long time,? ) what this seller said was that they were just interested in new users that did not know the difference between a good product and a poor product,

(I know it sounds crazy, but that is what this person was doing,)

Charging a huge price, (compared to other products that do the same thing)

And this person did not care that they were treating their customers poorly, that is something that is really important, so when you are considering how to plan out your API, make sure it does two things.

1. provides value in a product that others cannot get for free.
2. creates a process that discourages buyers from trying to steal the product.

Again it is easier said than done, I have been developing an API system for this exact process for three months now and it is not yet perfect, in fact like I said earlier it is impossible to develop a perfect system, but you can slow them down and that is really something that you want to do.

Definitely use an activation code, but I'd have it sent to their email. You can set this up to be done automatically.

Sounds like a good plan, looks like the biggest challenge will be integration with clickbank,