Strangely enough I think "Hand in hand" would have been greater in Communiqué. It's like it was meant for this album musically.
I have always thought this album lacked one more song or two.
I'd never previously considered this, but maybe it would have been best if Hand In Hand had swapped albums with Portobello Belle. Hand In Hand is more of a straightforward love/break up song and therefore doesn't quite fit the story-based lyrics of the rest of the album, and as you say is probably the closest in sound to Communiqué on Making Movies. It also By contrast, Portobello Belle has vivid lyrics rich with imagery, more like the other songs on Making Movies, and was given a more 'rocked up' arrangement in later live performances so perhaps would have been better suited to the later album’s sound and theme.
One other aspect of this album is that I sometimes wonder whether working with Bob Dylan on Slow Train Coming somehow influenced Mark's writing on Solid Rock and to a lesser extent Hand In Hand. I definitely don't think Solid Rock is a religious song, but the song's title and lyrical theme do invite comparisons to the parable of the wise and foolish builders. Hand In Hand is less obvious but I think the first and final verses have a somewhat biblical feel, specifically the 'writing on the wall' and 'forgive this dirty town' lines.
In my opinion the ideal length for an album is between 35-50 minutes, with a 'sweet spot' between 40-45 minutes - many classic albums seem to fall within this range (Dark Side of the Moon, Led Zeppelin IV and Who's Next are three that readily spring to my mind. Interestingly, the first DS album, Communiqué and Love Over Gold are all within this range too). I find anything less than 35 minutes nearly always seems too short regardless of the quality of the material. Above 50 minutes, there is a double whammy as the inclusion of filler tracks becomes more likely and it gets harder to maintain interest in the music for a longer period of time if there’s no theme or story linking the tracks. I find this becomes particularly noticeable if the weaker tracks are mostly towards the end of the album. I do think non-conceptual double albums, or albums with runtimes over 1 hour, can work, but only in specific circumstances - either for a prolific artist at the peak of their powers (Blonde On Blonde) or an artist with a wide musical palette that has songs in many different styles (Physical Graffiti). Unfortunately, the former is inherently rare and not that many artists can pull off the latter either. In general, I do think that longer albums (both in runtime and number of tracks) in the CD era have reduced the likelihood of a ‘perfect’ album with great music from start to finish.