I trust that all is going well over at WHMCS, and I truly hope that your business is going from strength to strength.
Could I please suggest that you consider a.minor improvement that I strongly believe would improve a significant feature of your software.
May I please propose that you improve the layout of the domains page where the TLD's are listed in a table, along with the product add-ons, and the pricing modification.
To be more precise about what I am proposing, I believe the page is located here in the public_html directory - 'configdomains.php'
What could be improved?
At the present time if you opt to list an extensive list of domains 100+, the list becomes very long and cumbersome to navigate, and it also presents issues for the server when any changes are made, and the 'save' button is clicked. Some servers (depending on their hardware specs) wouldn't be able to handle such a large request, and may interpret such a network request as being potentially malicious.
What would need to be changed?
The only change that would need to be made would be to add a page breakdown option whereby pages are added according to a set number of domains, so you would list 50 domains on page one, the next 50 on page two etc... This would considerably speed up page load times, would improve page navigation speed, and would also help server resources to process the request a lot better. You could also implement an ajax script whereby you would click a button to 'show more domains' and then the domains are loaded dynamically (without reloading/refreshing the page).
The above suggested improvement would improve the overall service, and user experience design of the system back-end, and would also improve the exchange of data between the host, and the client.
Thank you for considering this request, and if I can be of any assistance in helping to provide more information at all on the above request please do not hesitate to contact me, and I'll be only too happy to help further.