If you're gonna use it with 8.5, then I think the 122 is maybe the best.
And what you say about needing a lot of power makes me think. The Aero has a "short rocker". It can get going early but requires the rider to get back and use the chop or fin drive if you have a big fin to free the nose. If the rider just pushes the board, it will indeed take a lot of power before it releases. This gets progressively more difficult the more sail you use (and the heavier you are).
The Futura has a longer rocker and in an equivalent size if will require less of that driver input and get going easier. So if you want to have earlier planing in a small size board, the Futura will be better.
But as you say, technique is improving every day. With that positive attitude you will have good time on the Kode too. And if you're after the feel and maneuver ability of the Kode, it might be worth to work some more on getting going.
Fins: 36cm will certainly be too small with your biggest sail, but still probably good for your smaller sails. These sizes have tuttle boxed and you can find a lot of options in the Drake program. If you want drive you could for example try some of the fins from the Futura range.