Hey there. Yeah, part of the reason I redesigned Dominic was to make him more visually appealing, but I also did it to give him a look more like I was originally trying to achieve as well as use a different generation of figure that would give me access to more assets I can use with him.
You don't need to worry about Owen - he is romanceable.
Dominic isn't taking up anyone's spot because every character was designed from the ground up to play a specific role. If he wasn't there, it doesn't mean Will would get a romance, it just means either there'd be one less romance or there would be an entirely different character who was created specifically to cover the archetype.
It seems you're not sure which guys have a romance, so I'll clear that up for you. The 10 romanceable guys are: Alex, Asher, Dominic, Evan, Griffin, Isaiah, Marco, Matt, Owen, and Riley. Only 6 main characters have a story that won't lead to a romance: Julian, Leo, Mafia, NC17, Tomas, and Will.
But just because those last 6 won't lead to a romance, it doesn't mean they will just be one-night stands with no story. The only guys who are purely hookup characters are the ones with a Grind'm scenario.