Yeah, FT plans tend to recommend motors "on the larger side" (to put it mildly). For example: the FT Simple Storch page recommends Power Pack C, with FT Radial 2218 1180kV Brushless Motor, and in turn the motor's page says it's recommended for planes in the 200-600g range. That's INSANE. In
THIS VIDEO, a guy did a wonderfully detailed test of this motor, and the results were (in general) over 300W of power and over 1000g of thrust! In almost any configuration!
On the other hand, I was flying my Storch, AUW in 750-800g range, using 40g motor with approx. 450-500g of thrust - and those are numbers suitable for learning. I obviously went even further and tested HexTronik 24g motor - 80W peak power, 250g of thrust max (from my experience, the manufacturer states 400g but I did not confirm that), and you know what? It was still perfectly flyable. If you find this hard to believe, please
WATCH THIS. That's a clear and easy 60g of saved weight, on a motor alone; add smaller ESC and battery to it and you can reduce the AUW by 100g or more - and on top of that, make it cheaper
Power Pack B is much closer to what I would recommend for the Storch. FT Flyer, in it's original size, is supposed to weight less than half of that, which will make it overpowered - and that's not a good thing, despite of what some of our american friends might say
In such case I would recommend looking for smaller motor, as a first, second and third option. And only if neither of those is possible - increase the size of the plane. But not too much. Remember that the original FT Flyer don't have any wing support, therefore the max wingspan is somewhat limited. 25% increase seems to be a reasonable compromise; anything above that may require adding struts or spars, and therefore weight.
Good luck, and have fun.