Hi anchorpoint
I am the Sunova Mascot/Pimp, so here's my take on some of your choices.
Either Sunova will work, surf wise and float wise.
the 8'10 Speeed will be the tippier of the 2 at 29" wide, but a better flat-water paddler.
the 8'10 Flow is stable and rips, but tends to yaw when paddling
Another Sunova that you might want to consider is the 8'10 Skate (143 liters)
I just got the 9'2 Skate (for winter) after riding the 8'8 XL and loving it. (I am 107 kg)
The Skate is awesome in small to medium surf, super stable and paddles easily.
Low rocker moves easily on small waves or flat-water.
Enough curve in the rails to turn easily, but still paddles straight.
My 9'2 Skate before a flat-water trip
This board gets all my thumbs up!