There would be somewhat less overhead to having a single animated "pump" which is responsible for updating everything else on a card.
Have you tried enabling the script profiler (Decker -> Script Profiler) to confirm that it's scripts which are slowing things down? Having a large number of widgets shown at any given time (or particularly large canvases) can also start to stack up.
If you're updating large numbers of widgets individually- like lots of separate fields displaying stats- you might find that it's more efficient to replace them with multi-line rich-text fields or grid widgets, both of which can be useful for displaying formatted bulk data. There's no hard-and-fast rule about the best way to approach things; you may need to experiment. If you find any particular operation which seems unusually slow, and you can provide me with a minimized example, I can investigate and possibly improve Decker's performance.