Piros thanks for the reply mate are you talking about the thruster set or quads ? I use the thruster set up . If you go to shapers you can get the S9 & 7 to suit either box . If you want to run the quad try what Wazza suggested I found that set really good on the PSH's , are you on the 9-2 ripper or wide ripper ?
Comes back to preference on quads and thrusters , the quads always feel more drivey at first but the thruster lets you pivot more creating the speed that way. For more comparisons the S9 are similar in size to the Future T1's so ether way that should be the size at the front regardless. The T1's are a stiffer solid glass fin with a slightly wider base where as the the S9 is a composite with more flex which makes it a bit easier to break the tail free but grab quickly again.
The Future AM2's are similar size to the S7's or your Rubens , you can also try those in the front if they feel big but it is myth that Sups need big fins front & back. If you do pick quad drop those rear fins down in size. The Simon Anderson (SA4) Future quad set is good but I would still reduce the size of the SA4 rears.
Just remember with the PSH they like the push from the tail so get your back foot onto the kick to get that board on its rail to squeeze out the drive. It's your great you're trying different fins. I used to surf with a box of fins on the beach and change them after a couple of waves. I've been very fortunate to ride & test heaps of boards and the fin set up I found best for me is a Thruster set up with the S9's in the front and a S9 or 7 in the rear.
This is video I did about a year ago when I first started riding a thruster set up and it explains about the Jackson Close fins.