Franky, I think Apple needs to decide whether this rumoured rugged model is simply a more robust AW or a true sport watch.
For it to resonate with athletes and succeed beyond Apple fanboys, it will need to improve on metrics (even more than watchOS9) such as recovery time, on-device training, race course predictions, etc. Additionally, athletes prefer buttons over touch displays. And buttons are things Apple looks to remove.
Of course given Apple's marketing prowess and reach, even limited success is relative. So even if it's the same design with a larger titanium casing, it will be sell in the millions.