I would be highly surprised if that were an issue. You should easily be able to get 1000+ sales. By way of comparison MonsterInsights has 3 MILLION free users and must be doing good with pro sales. It indicates that the demand is there.
One issue I have found with Better Analytics for WP is that its hard to find on the wordpress.org plugin repository. You really have to actively search for it. Consider to add some more tags that rivaling plugins use like 'wordpress analytics'. The review score is 4 stars while most other plugins have 4.5 - 5 stars. These negative reviews are because support requests have gone unanswered
here and
here. Negative reviews dampens use of the free version to only 5k active installs and therefore sales of the pro version.
On the wordpress.org page you do not describe the best parts of the pro features. That becomes only visible AFTER the potential customer goes to your website. But only the ones who have decided to go for the Pro version will click on the link. If you put the entire description of the pro features on the wordpress.org page then many more of those 5k users will become customers. If you do not advertise why your plugin is great, then you will not get the sales.
3rd thing that IMHO would increase your sales is to let guests buy the addon before registering. You want the buying process to be as frictionless as possible. WP users are alien to XF1. Forcing them to first do forum registration will cut down sales.
I can tell you from experience that if you have something similar to how this abandoned (popular) addon works, then this will increase your sales:
Note: The Lite/Free version is available on our website, choose the "Lite" option on the product page. How many paid subscriptions are you losing each month because your users don't know the benefits of purchasing a user upgrade? Do they even...
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