I read you all and kept working 
and I have some results
Search List screen
I worked on the visibility of the list which has no filter.
The list is now shown only if letters are written in the search field. The result is very correct.
Charts & Count
Counts and charts are since the begging filtered. I followed Do’s and Don’ts for app speed recommendations and have dispatched every charts and counts on different screens and keeping filtered respective Category (only 2 categories exists). It’s getting better results … i would said “not the best” but “not that bad” for some of them.
Working on a chart that sums 6 months of rows still lags the navigation between screens 
I keep going … and let you know
@Victor As I say, I use filtering on every results i want, by Logged User, Category, Step, Dates… I don’t work on mass for the charts & stats component.
Only the Agenda screen is working for the moment with all logged user’s prospects. I didn’t try to filter them yet.
2nd Search List screen
For my other specific search screen for prospect management where user can filter by Category and Step and then goes to another management screen, I used Simple list component and not Custom List component. On custom list component I found the lazy loading option and by activating it, it’s getting better also not the best but It goes better.
Thanks for your Help. I keep going.
Next Step the Agenda