Drupal website improvements and enhancements with high attention on mobile performance

My project consists in making several improvements/ enhancements to my Responsive Drupal website:

1. Migration onto a new platform and reconfiguration
2. creating changes on the IA and site structure and testing them on mobile an tablets
3. Creating a new content type to host multimedia: an image gallery showing a portfolio
4. Creating another content type to host data picked up from the API of a 3rd party tool via XML.Once this content type is ready, create 4 pages with it.
5. Helping with the troubleshooting of the translation and internationalisation Drupal modules already installed. Test and ensure that translated content can be added. Translated content will be shown via subdirectories, eg: /fr/ for french
6. Troubleshooting a couple of glitches on the site's blog
7. Searching, finding and installing a Drupal module to help with adding tabbed content on certain pages
8. Searching, finding and installing (and configuring) the FAQs Drupal module and present it on a sample page

If you are interested, I invite you to read the attached sheet with the full requirements for each of those tasks listed above.

All development work to be done on the site should take into account the imperative need for the website to be not just responsive but perform well on mobile.