Hey,
I am Anthony, I can absolutely convert your Joomla website to a responsive WordPress website maintaining the look and all data. I have done similar projects, and I can carry out this project in a timely and professional manner. I estimate 7-12 days max to finish the project to your satisfaction.
Regarding the slider/slideshows, I can implement something simpler that allow you to upload images per slideshow at once instead of one by one.
For clarification, will you provide access to the existing website?
I look forward to hear from you.
Kind Regards,
Anthony