Others have already given some valuable suggestions, so I will focus on what's worked well for us.

(To set the context: We have two businesses around WordPress & WooCommerce, 30+ premium plugins, 250k+ active installs)

1. Free plugin on WP.org, and a Pro upsell. Works really well. But make sure to optimize your plugin's description / readme.txt file.

2. Organic inbound traffic - search engines etc. In depth content will get you visitors. This still works!

3. Building relationships - like Rebecca mentioned. If enough people know you, they may recommend your plugins to others - even if they themselves are not the users.

4. Focus on UX, build a better product. There are just too many plugins out there. You must solve a deep user pain to be able to succeed.

Hope this gets you started..

BTW, I spoke about building and marketing WP plugins at WordCamp Mumbai in 2016.. I think you will still find the talk relevant:
https://wordpress.tv/2017/06/30/nirav-mehta-build-and-they-wont-come-wp-plugin-marketing-tips/

All the best!

If you are going to lead the workshops:

Start with personal branding. Workshops and coaching are by experts and I'd recommend building a personal brand first. People should build trust in you. Then your offerings.

Each offering that you have - a workshop, a coaching program etc. - should have it's own branding. You may even have separate websites for each of your offerings.

If you are only organizing the business and not going to lead the programs yourself: then you got to do a corporate branding. So people relate to the organization more than individuals delivering the programs.

The coaching / self help / personal development / health industry is full of examples of both branding strategies. If you study a few cases, and their business models, you will gain better insights on why they chose their branding strategy. And you can even question if the strategy worked or not.

I hope this gives additional perspective to what you are thinking.

Feel free to contact me if you want to discuss this further.

Couple of months may be a very short time to warm up a cold list. Especially if you don't have any existing auto responder sequence / regular email follow ups with the people on the list.

Creating a few segments, and restarting communication would be the obvious first step. Acknowledge your lack of communication and reconnect with your audience. Ask them about how they're doing with their original purchase from you. Offer to help.

Then start content / value driven emails. May be a couple of webinars in between; and social media campaigns.

Slowly raise their interest in your upcoming product. Talk about the pain points, a "hero" story may be.. And progress into your launch sequence.

I believe WordPress can be great for a membership site.

I've seen a few recipe plugins for WordPress, and there are a ton of membership plugins. Most will allow you to restrict content based on membership levels. So you can create a custom post type for recipes (most recipe plugins would do this), and configure the membership plugin to restrict access based on your business rules.

Chris Lema has awesome reviews of membership plugins (https://chrislema.com/memberships-plugins/). Chris is also on Clarity and he knows his stuff. So feel free to dig through his reviews and connect with him.

One suggestion: Don't get bogged down / excited by features of membership plugins. Focus on your customers, their needs and pain points.

"Oh.. this plugin can do this.. So let me add that feature to my business" - is wrong line of thinking!

It's been a year to the original question, so not sure if you're still looking for an answer to this. Yet..

From your description, it seems like you want to build a web app that manages multiple WooCommerce stores from a single interface.

I saw a video demo of such a solution a few weeks ago. It's called Multishop - https://multishop.io/

There is also a proposed fork to WooCommerce to support multiple sites - http://woomu.org/

And here's a similar idea on WooCommerce Ideas board - http://ideas.woothemes.com/forums/133476-woocommerce/suggestions/4295981-multiple-shops-one-backend

We build some popular WooCommerce extensions. One of our plugins - Smart Manager - lets people manage products, inventory, orders and customers easily. Smart Reporter does advanced reporting on WooCommerce.

We have also looked at WC API and upcoming WP API.

It's great that you've setup WC multisite on your own. But if you don't like PHP, and want to rely on WC / WP APIs, I believe this is going to be a difficult project.

In all likelihood you'd need your own plugin. WC / WP APIs may not be sufficient for your needs. Another challenge is maintaining compatibility with ever growing list of WC extensions. So if you plan to build the web app for anyone (rather than a set of WC installs you control), you will need to invest significant energy in managing compatibility and updates.

And if the reason you wanted to build your app was to provide a simpler UI / UX, you can still build a plugin that hides all complexities. Or contribute to WooCommerce core with your suggestions / ideas / patches.

HTH!

It's not clear from your question, but I'm assuming your client wants a frontend built in WordPress for this data. So assuming you'd be building a custom plugin.

Depending on the data structure, it may be best to keep this data in its own tables - within the same WP database if you like.

You can indeed create custom post types in WordPress and store any kind of data. But you may hit performance bottlenecks when you want to perform searches or want data in particular format.

We've built and tested some of our plugins with millions of rows of data. When we need higher performance, we've used our own tables inside WP. Rather than relying on WP's core data structures.

Hope this helps. And I'd be happy to answer any specific questions you may have.

Continuing on what Michael said...

I'm not aware of a ready solution that will do all that you want.. Though it is the line of development we have for our own WordPress plugin - Icegram - http://www.icegram.com.

Icegram shows different ads / call to actions / lead capture forms to users. And includes flexible targeting rules. You can actually create your own plugin that adds more targeting rules. So you can extend Icegram to support targeting by demographics you mentioned.

Icegram is free. With paid addons. You may want to give it a try.