Howdy, interesting you find the fusion tippy at 31 " WIDE> I have the Surf Wide body 8 8 AT 32 " wide body and find it super stable .
I came down from a Fanatic all wave 9 6 2013 model, that has the same stability but nowhere near the manoeuvrability. My wife now uses the Fanatic, loves it. Basically, I suggest as usual. 1) if you have the fusion stick with it and get the hours in to improve technique.
2) If it feels off and you just can't get the hang of it, demo, 3) demo, 4) demo! The best part of SUP is the demo of new boards then go with what your feet tell you.
Conditions do vary, and some days are easier than others. But a demo over a week or two in the surf not flat water Is the best way I can suggest forward.