We have a theme using understrap, which is the underscores framework with bootstrap. The bootstrap menu is not too freindly, it doesn't go down to another sub-menu level. When we enabled it with some hacks found around the web, it partially works, but not on mobile and it is difficult to navigate on desktop. The reason why we think we would like to switch to the twentyseventeen menu is because it uses the same underscore framework and we saw it has already been done: [login to view URL]
We are also open to fixing this menu so it works better on mobile and has ability to go to 2 levels instead of just one dropdown. Should work on mobile and desktop, easy to select sub-levels.
We need this done within a few hours. Site link available upon request, but it uses [login to view URL] with their child theme.