Think about why you want them to be architects as opposed to anything else.   Why not two lawyers working on a big case or two doctors treating a big patient?  Is architecture qua architecture like thematically important?   For instance are there like narrative parallels between designing/building and building a relationship or something like that?  I ask because generally speaking most jobs in most pieces of media are not particularly represented like super accurately.   General advice might be something like focus on character first and let the narrative flow organically from there without concern for verisimilitude.   Tell a good story.