You have an app with these controls you want to use? If so then if the tablet is new enough to support split screen mode (2 apps on display at the same time) you might be able to produce some approximation that way.
Otherwise I think the simplest solution would be an app which provided a small tab or swipe area that you can position on some edge of the screen and use that to pull your controls out when needed. There are various apps that provide little custom menus that work like that, so I know it's possible. And that wouldn't require a custom ROM.
If you really want the controls always on screen, as opposed to always available, then that's harder. They'd interfere with other apps' UIs unless you could shrink those apps to the space above them, which might be possible if the multi-window feature is flexible enough (I almost never use it, so don't know), or else that may need a custom ROM, but a lot more custom than any I've ever met. (I'm assuming here that these controls are larger than could be fitted by some radical customisation of the navigation bar: I know that a degree of customisation of the nav bar can be acheived with an app, but don't ask me how it's done).
