A smaller version of the 104 would be nice to have, just to calm my wife down a bit on my buying Sinn watches... a 36 mm would be nice on her wrist and the ETA 2436 or whatever Selitta with their 25.6 mm diameter allows this size. A count-up bezel option would also be nice, and somehow give lume to the hour marking that can allow even better night visibility, I mean either dropping the lume at 3 completely, or luming a thicker area at 12 - or both. Or luming only 3, 6, 9 and a thicker 12. On the IWC Fliegers works this quite well.
I'd buy such a watch in the first instance. And this size is still wearable for men too - remember, some of the Datejusts and the Turn-O-Graph is 36 mm too...
So, all in all, we haven't seen a new sporty watch by Sinn since ages... I think lots of 103 St, 103 St Sa, 104, 203, 203 Arktis, 303 and some of the early EZM owners would be happy with this.