There are some serious bugs in how the SuiteP theme fails to respond properly to varying browser screen sizes resolutions, these bugs make some buttons on certain screens unusable due to improper wrapping of certain parts of the user interface, when they shouldn't ever wrap to the next line but instead auto resize in a sensible way so that they are still usable.
The SuiteP theme is supposed to be responsive but it fails in certain corner cases. It needs to respond to all corner cases, without allowing bugs in the theme to let html elements overlay one another in unplanned ways, thereby blocking user access to click or tap on buttons/links on the web interface.
Here's a screenshot with highlights on the problem areas.

Working with SuiteCRM in the SuiteP is far more difficult than would be with a fully responsive theme, on mobile, tablet and desktop.
@chris001 #3025 i found this.. maybe it solves a part of your problem
Thanks @Mausino that PR #3025 solves a a part of the problem, that PR could be improved to degrade to one hamburger menu plus one nav menu filter for the current module. The rest of this issue would be solved with more accurate dynamic calculation of the appropriate responsive size of each element, spacing, and padding in the page, in the moment, to prevent page content spilling over beyond the screen page width and breaking responsiveness with the horizontal scroll bars.
Spoke too soon. It only works on a few lucky menus where the calculation works in spite itself. On about 95% of the menus, PR #3025 miscalculates the space it has for the navigation menu, causes the navigation menu to wrap to the next line, overly other links, and make them impossible to access.
The code fails to account for the width of the "module filter menu" which is the name I give to the red colored menu added to the navigation menu, just to the right of the "Home" icon, and this "module filter menu" only appears, and takes up some of the top navigation menu space, when you're inside a module. Example, "Security Groups Management" module has its own menu
The reason is, that "module filter menu" is added by the theme, AFTER the ajax request completes. So this PR is lacking the information on the true full width of the navigation menu INCLUDING the late addition of the "module filter menu".
I read the source for the SuiteP theme. The problem is, it's not fully following the rules of responsive web design, so issues like this one.
There should be no Smarty PHP for-loop for generating the tables - that was the thing to do back in 2004 when sugarcrm first came out. The dashlets layout position on the page now in 2017 should be decided by the browser, which as we know, look to the CSS3, bootstrap, media queries, makes fast native math calculations, and places them natively in rows, or one below the other in narrow width screens, this is true responsive web design.
Thanks for your observations chris and you are right tables shouldn't be used as heavily as they do but there are too many areas of the SuiteCRM instance that use them and would require a larger overall and working on all themes (can't have tables in one theme and not in another). We are aware of the limitations of tables, and we have already begun replacing them with more responsive elements - and this will continue in future releases.
I've got some recommendations. This should be discussed. Will make a new issue.
At least, SuiteP Home page template needs to be updated to completely apply responsive css html to the dashlet layout. They're spilling over the right limit of the page when they should wrap so they stay on the page within the width limit.