I have both, the 9 8 Starboard is way more stable than the ripper. I am 105kg so you might find it easier.

As first board not sure, would be ok on flat calm days possibly but throw it chop and swell maybe a different story.

If all you are going to do is ride waves it could be worth the pain though. The PSH boards are the sh1t in the surf.

I know someone started on a 9 3 ripper so it can be done. AA would be the man to talk to. Demo if you can.

I've got the same board as Hilly's ('09 *board rounded pin) and find that it's super-stable in ideal & close-to-ideal conditions. However, it's apparently a little less stable than the '08 swallow-tail.
I saw a guy out on one for the first time on the weekend. He's taller & heavier than me & had come down from an 11-footer (or thereabouts I think) & was finding it to be pretty tippy. But within half an hour he looked fine on it.
I tried mine out in 20 knot onshore chest-high waves; fell off a lot just paddling but it was doable.
I've also had a paddle on Hilly's PSH in glassy small conditions & was surprised at how stable it is (I'm a bit lighter at 73 kgs & 174 cms height).
I'm sure the PSH would be a better performer in serious waves, but for an all-rounder in Perth for my size I'm pretty happy with the 9'8".
I'll update my review next time I get a chance to get out of the city for some real waves (only been down south once on the *board in the 7 weeks that I've had it)